Rapid and efficient generation of a transplantable population of functional retinal ganglion cells from fibroblasts

Glaucoma and other optic neuropathies lead to progressive and irreversible vision loss by damaging retinal ganglion cells (RGCs) and their axons. Cell replacement therapy is a potential promising treatment. However, current methods to obtain RGCs have inherent limitations, including time-consuming procedures, inefficient yields and complex protocols, which hinder their practical application. Here, we have developed a straightforward, rapid and efficient approach for directly inducing RGCs from mouse embryonic fibroblasts (MEFs) using a combination of triple transcription factors (TFs): ASCL1, BRN3B and PAX6 (ABP). We showed that on the 6th day following ABP induction, neurons with molecular characteristics of RGCs were observed, and more than 60% of induced neurons became iRGCs (induced retinal ganglion cells) in the end. Transplanted iRGCs had the ability to survive and appropriately integrate into the RGC layer of mouse retinal explants and N-methyl-D-aspartic acid (NMDA)-damaged retinas. Moreover, they exhibited electrophysiological properties typical of RGCs, and were able to regrow dendrites and axons and form synaptic connections with host retinal cells. Together, we have established a rapid and efficient approach to acquire functional RGCs for potential cell replacement therapy to treat glaucoma and other optic neuropathies.

Human retinal organoids with an OPA1 mutation are defective in retinal ganglion cell differentiation and function

Autosomal dominant optic atrophy (ADOA), mostly caused by heterozygous OPA1 mutations and characterized by retinal ganglion cell (RGC) loss and optic nerve degeneration, is one of the most common types of inherited optic neuropathies. Previous work using a two-dimensional (2D) differentiation model of induced pluripotent stem cells (iPSCs) has investigated ADOA pathogenesis but failed to agree on the effect of OPA1 mutations on RGC differentiation. Here, we use 3D retinal organoids capable of mimicking in vivo retinal development to resolve the issue. We generated isogenic iPSCs carrying the hotspot OPA1 c.2708_2711delTTAG mutation and found that the mutant variant caused defective initial and terminal differentiation and abnormal electrophysiological properties of organoid-derived RGCs. Moreover, this variant inhibits progenitor proliferation and results in mitochondrial dysfunction. These data demonstrate that retinal organoids coupled with gene editing serve as a powerful tool to definitively identify disease-related phenotypes and provide valuable resources to further investigate ADOA pathogenesis and screen for ADOA therapeutics.

Neural cell isolation from adult macaques for high-throughput analyses and neurosphere cultures

The low number of neural progenitor cells (NPCs) present in the adult and aged primate brains represents a challenge for generating high-yield and viable in vitro cultures of primary brain cells. Here we report a step-by-step approach for the fast and reproducible isolation of high-yield and viable primary brain cells, including mature neurons, immature cells and NPCs, from adult and aged macaques. We describe the anesthesia, transcardial perfusion and brain tissue preparation; the subsequent microdissection of the regions of interest and their enzymatic dissociation, leading to the separation of single cells. The cell isolation steps of our protocol can also be used for routine cell culturing, in particular for NPC expansion and differentiation, suitable for studies of hippocampal neurogenesis in the adult macaque brain. The purified primary brain cells are largely free from myelin debris and erythrocytes, paving the way for multiple downstream applications in vitro and in vivo. When combined with single-cell profiling techniques, this approach allows an unbiased and comprehensive mapping of cell states in the adult and aged macaque brain, which is needed to advance our understanding of human cognitive and neurological diseases. The neural cell isolation protocol requires 4 h and a team of four to six users with expertize in primary brain cell isolation to avoid tissue hypoxia during the time-sensitive steps of the procedure.

Generation of self-organized autonomic ganglion organoids from fibroblasts

Neural organoids have been shown to serve as powerful tools for studying the mechanism of neural development and diseases as well as for screening drugs and developing cell-based therapeutics. Somatic cells have previously been reprogrammed into scattered autonomic ganglion (AG) neurons but not AG organoids. Here we have identified a combination of triple transcription factors (TFs) Ascl1, Phox2a/b, and Hand2 (APH) capable of efficiently reprogramming mouse fibroblasts into self-organized and networked induced AG (iAG) organoids, and characterized them by immunostaining, qRT-PCR, patch-clamping, and scRNA-seq approaches. The iAG neurons exhibit molecular properties, subtype diversity, and electrophysiological characteristics of autonomic neurons. Moreover, they can integrate into the superior cervical ganglia following transplantation and innervate and control the beating rate of co-cultured ventricular myocytes. Thus, iAG organoids may provide a valuable tool to study the pathogenesis of autonomic nervous system diseases and screen for drugs, as well as a source for cell-based therapies.

Comparative analysis of electroretinogram with subdermal and invasive recording methods in mice

Electroretinogram (ERG) is the most common clinical and basic visual electrodiagnostic test, which has long been used to evaluate the retinal function through photic stimulation. Despite its wide application, there are still some pitfalls often neglected in ERG recording, such as the recording time point, active electrode location, and the animal strain. In this study, we systematically analyzed and compared the effects of multiple factors on ERG, which would provide an important reference for ERG detection by other investigators. ERG was recorded using the Celeris D430 rodent ERG testing system. The amplitudes and latencies of a wave, b wave and oscillatory potentials (OPs) recorded from different electrode locations (subdermal and invasive), different times of day (day time 8:00 to 13:00 and night time 18:00 to 23:00), bilateral eyes (left and right), and different mouse strains (C57 and CD1) were analyzed and compared. Our results revealed that ERG was affected by active electrode locations and difference between day and night, while OPs seemed not to be influenced. There was no significant difference in the amplitudes or latencies of ERG and OPs between left and right eyes, irrespective of measurements at day or night, or which method was used. Compared to C57 mice, both ERG and OP responses were significantly decreased in Brn3b^AP/AP mice, a model for retinal ganglion cell (RGC) loss. In addition, there were some non-negligible differences in visual responses between C57 and CD1 mouse strains. Our results suggest that the invasive procedure is a reliable method for evaluating the visual function including VEP, ERG and OP responses in mice. Moreover, these comparative analyses provide valuable references for future studies of mammalian visual electrophysiology.

[Clinical features of 19 patients with SIL-TAL1-positive T-cell acute lymphoblastic leukemia]

Objective: To assess the clinical characteristics and prognosis of patients with SIL-TAL1-positive T-cell acute lymphoblastic leukemia (T-ALL) . Methods: The clinical data of 19 SIL-TAL1-positive T-ALL patients admitted to the First Affiliated Hospital of Soochow University between January 2014 and February 2022 were retrospectively computed and contrasted with SIL-TAL1-negative T-ALL patients. Results: The median age of the 19 SIL-TAL1-positive T-ALL patients was 15 (7 to 41 years) , including 16 males (84.2%) . SIL-TAL1-positive T-ALL patients had younger age, higher WBC, and hemoglobin compared with SIL-TAL1-negative T-ALL patients. There was no discrepancy in gender distribution, PLT, chromosome abnormality distribution, immunophenotyping, and complete remission (CR) rate. The 3-year overall survival (OS) was 60.9% and 74.4%, respectively (HR=2.070, P=0.071) . The 3-year relapse-free survival (RFS) was 49.2% and 70.6%, respectively (HR=2.275, P=0.040) . The 3-year RFS rate of SIL-TAL1-positive T-ALL patients was considerably lower than SIL-TAL1-negative T-ALL patients. Conclusion: SIL-TAL1-positive T-ALL patients were connected to younger age, higher WBC, higher HGB, and poor outcome.

Mitochondrion-located peptides and their pleiotropic physiological functions

With the development of advanced technologies, many small open reading frames (sORFs) have been found to be translated into micropeptides. Interestingly, a considerable proportion of micropeptides are located in mitochondria, which are designated here as mitochondrion-located peptides (MLPs). These MLPs often contain a transmembrane domain and show a high degree of conservation across species. They usually act as co-factors of large proteins and play regulatory roles in mitochondria such as electron transport in the respiratory chain, reactive oxygen species (ROS) production, metabolic homeostasis, and so on. Deficiency of MLPs disturbs diverse physiological processes including immunity, differentiation, and metabolism both in vivo and in vitro. These findings reveal crucial functions for MLPs and provide fresh insights into diverse mitochondrion-associated biological processes and diseases.

Notch signaling determines cell-fate specification of the two main types of vomeronasal neurons of rodents

The ability of terrestrial vertebrates to find food and mating partners, and to avoid predators, relies on the detection of chemosensory information. Semiochemicals responsible for social and sexual behaviors are detected by chemosensory neurons of the vomeronasal organ (VNO), which transmits information to the accessory olfactory bulb. The vomeronasal sensory epithelium of most mammalian species contains a uniform vomeronasal system; however, rodents and marsupials have developed a more complex binary vomeronasal system, containing vomeronasal sensory neurons (VSNs) expressing receptors of either the V1R or V2R family. In rodents, V1R/apical and V2R/basal VSNs originate from a common pool of progenitors. Using single cell RNA-sequencing, we identified differential expression of Notch1 receptor and Dll4 ligand between the neuronal precursors at the VSN differentiation dichotomy. Our experiments show that Notch signaling is required for effective differentiation of V2R/basal VSNs. In fact, Notch1 loss of function in neuronal progenitors diverts them to the V1R/apical fate, whereas Notch1 gain of function redirects precursors to V2R/basal. Our results indicate that Notch signaling plays a pivotal role in triggering the binary differentiation dichotomy in the VNO of rodents.

Identification of a New Mutation p.P88L in Connexin 50 Associated with Dominant Congenital Cataract

Congenital hereditary cataract is genetically heterogeneous and the leading cause of visual impairment in children. Identification of hereditary causes is critical to genetic counselling and family planning. Here, we examined a four-generation Chinese pedigree with congenital dominant cataract and identified a new mutation in GJA8 via targeted exome sequencing. A heterozygous missense mutation c.263C > T, leading to a proline-to-Leucine conversion at the conserved residue 88 in the second transmembrane domain of human connexin 50 (Cx50), was identified in all patients but not in unaffected family members. Functional analyses of the mutation revealed that it disrupted the stability of Cx50 and had a deleterious effect on protein function. Indeed, the mutation compromised normal membrane permeability and gating of ions, and impeded cell migration when overexpressed. Together, our results expand the pathogenic mutation spectrum of Cx50 underlying congenital cataract and lend more support to clinical diagnosis and genetic counseling.

An optimized procedure to record visual evoked potential in mice

Visual evoked potential (VEP) is commonly used to evaluate visual acuity in both clinical and basic studies. Subdermal needle electrodes or skull pre-implanted screw electrodes are usually used to record VEP in rodents. However, the VEP amplitudes recorded by the former are small while the latter may damage the brain. In this study, we established a new invasive procedure for VEP recording, and made a series of comparisons of VEP parameters recorded from different electrode locations, different times of day (day and night) and bilateral eyes, to evaluate the influence of these factors on VEP in mice. Our data reveal that our invasive method is reliable and can record VEP with good waveforms and large amplitudes. The comparison data show that VEP is greatly influenced by active electrode locations and difference between day and night. In C57 or CD1 ONC (optic nerve crush) models and Brn3b^AP/AP mice, which are featured by loss of retinal ganglion cells (RGCs), amplitudes of VEP N1 and P1 waves are drastically reduced. The newly established VEP procedure is very reliable and stable, and is particularly useful for detecting losses of RGC quantities, functions or connections to the brain. Our analyses of various recording conditions also provide useful references for future studies.

Deficiency of ribosomal proteins reshapes the transcriptional and translational landscape in human cells

Human ribosomes have long been thought to be uniform factories with little regulatory function. Accumulating evidence emphasizes the heterogeneity of ribosomal protein (RP) expression in specific cellular functions and development. However, a systematic understanding of functional relevance of RPs is lacking. Here, we surveyed translational and transcriptional changes after individual knockdown of 75 RPs, 44 from the large subunit (60S) and 31 from the small subunit (40S), by Ribo-seq and RNA-seq analyses. Deficiency of individual RPs altered specific subsets of genes transcriptionally and translationally. RP genes were under cotranslational regulation upon ribosomal stress, and deficiency of the 60S RPs and the 40S RPs had opposite effects. RP deficiency altered the expression of genes related to eight major functional classes, including the cell cycle, cellular metabolism, signal transduction and development. 60S RP deficiency led to greater inhibitory effects on cell growth than did 40S RP deficiency, through P53 signaling. Particularly, we showed that eS8/RPS8 deficiency stimulated apoptosis while eL13/RPL13 or eL18/RPL18 deficiency promoted senescence. We also validated the phenotypic impacts of uL5/RPL11 and eL15/RPL15 deficiency on retina development and angiogenesis, respectively. Overall, our study provides a valuable resource for and novel insights into ribosome regulation in cellular activities, development and diseases.

In vivo Regeneration of Ganglion Cells for Vision Restoration in Mammalian Retinas

Glaucoma and other optic neuropathies affect millions of people worldwide, ultimately causing progressive and irreversible degeneration of retinal ganglion cells (RGCs) and blindness. Previous research into cell replacement therapy of these neurodegenerative diseases has been stalled due to the incapability for grafted RGCs to integrate into the retina and project properly along the long visual pathway. In vivo RGC regeneration would be a promising alternative approach but mammalian retinas lack regenerative capacity. It therefore has long been a great challenge to regenerate functional and properly projecting RGCs for vision restoration in mammals. Here we show that the transcription factors (TFs) Math5 and Brn3b together are able to reprogram mature mouse Müller glia (MG) into RGCs. The reprogrammed RGCs extend long axons that make appropriate intra-retinal and extra-retinal projections through the entire visual pathway to innervate both image-forming and non-image-forming brain targets. They exhibit typical neuronal electrophysiological properties and improve visual responses in RGC loss mouse models. Together, our data provide evidence that mammalian MG can be reprogrammed by defined TFs to achieve in vivo regeneration of functional RGCs as well as a promising new therapeutic approach to restore vision to patients with glaucoma and other optic neuropathies.

Widespread translational control regulates retinal development in mouse

Retinal development is tightly regulated to ensure the generation of appropriate cell types and the assembly of functional neuronal circuitry. Despite remarkable advances have been made in understanding regulation of gene expression during retinal development, how translational regulation guides retinogenesis is less understood. Here, we conduct a comprehensive translatome and transcriptome survey to the mouse retinogenesis from the embryonic to the adult stages. We discover thousands of genes that have dynamic changes at the translational level and pervasive translational regulation in a developmental stage-specific manner with specific biological functions. We further identify genes whose translational efficiencies are frequently controlled by changing usage in upstream open reading frame during retinal development. These genes are enriched for biological functions highly important to neurons, such as neuron projection organization and microtubule-based protein transport. Surprisingly, we discover hundreds of previously uncharacterized micropeptides, translated from putative long non-coding RNAs and circular RNAs. We validate their protein products in vitro and in vivo and demonstrate their potentials in regulating retinal development. Together, our study presents a rich and complex landscape of translational regulation and provides novel insights into their roles during retinogenesis.

Generation of self-organized sensory ganglion organoids and retinal ganglion cells from fibroblasts

Neural organoids provide a powerful tool for investigating neural development, modeling neural diseases, screening drugs, and developing cell-based therapies. Somatic cells have previously been reprogrammed by transcription factors (TFs) into sensory ganglion (SG) neurons but not SG organoids. We identify a combination of triple TFs Ascl1, Brn3b/3a, and Isl1 (ABI) as an efficient means to reprogram mouse and human fibroblasts into self-organized and networked induced SG (iSG) organoids. The iSG neurons exhibit molecular features, subtype diversity, electrophysiological and calcium response properties, and innervation patterns characteristic of peripheral sensory neurons. Moreover, we have defined retinal ganglion cell (RGC)-specific identifiers to demonstrate the ability for ABI to reprogram induced RGCs (iRGCs) from fibroblasts. Unlike iSG neurons, iRGCs maintain a scattering distribution pattern characteristic of endogenous RGCs. iSG organoids may serve as a model to decipher the pathogenesis of sensorineural diseases and screen effective drugs and a source for cell replacement therapy.

[Effects of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children]

Objective: To explore the effect of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children. Methods: From October to November 2017, 27 987 children aged 3 to 6 years old from 109 kindergartens in 11 cities of Hubei, Anhui and Jiangsu Provinces were selected by using the cluster sampling method. A total of 27 200 valid questionnaires which were completed by subjects' parents were collected. The emotional and behavioral problems of preschool children were collected by "strengths and difficulties questionnaire" and the parental rearing patterns were evaluated by the "Parental Behavior Scale". The differences in emotional and behavioral abnormality rates of preschool children with different characteristics were analyzed; with emotional and behavioral problems as dependent variables and parental support/participation and compulsion/hostility as independent variables, the multivariate logistic regression model was used to analyze the effect of parental rearing patterns and their consistency on the emotional and behavioral problems of preschool children. Results: The age of children was (4.35±0.96) years old, and 51.4% of children were 13 975 males. There were 24 634 (90.6%) urban children and 17 916 (65.9%) only children. Both parents with strong support/participation accounted for 14.9%, and those with poor support/participation accounted for 11.9%; both parents with strong compulsion/hostility accounted for 15.2%, and those with low compulsion/hostility accounted for 11.3%. The rates of emotional symptoms, conduct behavior, hyperactive behavior, peer interaction, total difficulty score, and abnormal prosocial behavior of preschool children were 9.5%, 9.5%, 18.2%, 24.5%, 11.2%, and 10.2%, respectively. The multivariate logistic regression model analysis showed that after adjusting for gender, only child, living area, family economic status, mother's age and education level, father's education level, and other factors, compared with fathers/mothers with strong support/participation and low compulsion/hostility and parents with strong support/participation and low compulsion/hostility, preschool children who had fathers/mothers with poor support/participation and strong compulsion/hostility or parents with poor support/participation and strong compulsion/hostility were more likely to have emotional symptoms, conduct behavior, hyperactive behavior, peer interaction, total difficulty score, and abnormal prosocial behavior (P<0.05). Conclusions: Parental rearing patterns and their consistency are related to the emotional and behavioral problems of preschool children.

A Novel Mutation p.S93R in CRYBB1 Associated with Dominant Congenital Cataract and Microphthalmia

Purpose: To identify the pathogenetic mutations in a four-generation Chinese family with dominant congenital cataracts and microphthalmia.Methods: A four-generation Chinese family with dominant congenital cataracts were recruited. Genomic DNAs were collected from their peripheral blood leukocytes and subjected to whole exome sequencing. The genetic mutations were identified by bioinformatic analyses and verified by Sanger sequencing.Results: Whole exome sequencing revealed a c.279C>G point mutation in the CRYBB1 gene which was further verified by Sanger sequencing. The nucleotide replacement results in a novel mutation p.S93R in a conserved residue of βB1 crystallin which is predicted to disrupt normal βB1 structure and function.Conclusions: We identified a novel missense mutation p.S93R in CRYBB1 in a Chinese family with autosomal dominant congenital cataracts and microphthalmia. This serine residue is extremely conserved evolutionarily in more than 50 βγ-crystallins of many species. These data will be very helpful to further understand the structural and functional features of crystallins.

Transcription factor Ptf1a in development, diseases and reprogramming

The transcription factor Ptf1a is a crucial helix-loop-helix (bHLH) protein selectively expressed in the pancreas, retina, spinal cord, brain, and enteric nervous system. Ptf1a is preferably assembled into a transcription trimeric complex PTF1 with an E protein and Rbpj (or Rbpjl). In pancreatic development, Ptf1a is indispensable in controlling the expansion of multipotent progenitor cells as well as the specification and maintenance of the acinar cells. In neural tissues, Ptf1a is transiently expressed in the post-mitotic cells and specifies the inhibitory neuronal cell fates, mostly mediated by downstream genes such as Tfap2a/b and Prdm13. Mutations in the coding and non-coding regulatory sequences resulting in Ptf1a gain- or loss-of-function are associated with genetic diseases such as pancreatic and cerebellar agenesis in the rodent and human. Surprisingly, Ptf1a alone is sufficient to reprogram mouse or human fibroblasts into tripotential neural stem cells. Its pleiotropic functions in many biological processes remain to be deciphered in the future.

Necessity and Sufficiency of Ldb1 in the Generation, Differentiation and Maintenance of Non-photoreceptor Cell Types During Retinal Development

During mammalian retinal development, the multipotent progenitors differentiate into all classes of retinal cells under the delicate control of transcriptional factors. The deficiency of a transcription cofactor, the LIM-domain binding protein Ldb1, has been shown to cause proliferation and developmental defects in multiple tissues including cardiovascular, hematopoietic, and nervous systems; however, it remains unclear whether and how it regulates retinal development. By expression profiling, RNA in situ hybridization and immunostaining, here we show that Ldb1 is expressed in the progenitors during early retinal development, but later its expression gradually shifts to non-photoreceptor cell types including bipolar, amacrine, horizontal, ganglion, and Müller glial cells. Retina-specific ablation of Ldb1 in mice resulted in microphthalmia, optic nerve hypoplasia, retinal thinning and detachment, and profound vision impairment as determined by electroretinography. In the mutant retina, there was precocious differentiation of amacrine and horizontal cells, indicating a requirement of Ldb1 in maintaining the retinal progenitor pool. Additionally, all non-photoreceptor cell types were greatly reduced which appeared to be caused by a generation defect and/or retinal degeneration via excessive cell apoptosis. Furthermore, we showed that misexpressed Ldb1 was sufficient to promote the generation of bipolar, amacrine, horizontal, ganglion, and Müller glial cells at the expense of photoreceptors. Together, these results demonstrate that Ldb1 is not only necessary but also sufficient for the development and/or maintenance of non-photoreceptor cell types, and implicate that the pleiotropic functions of Ldb1 during retinal development are context-dependent and determined by its interaction with diverse LIM-HD (LIM-homeodomain) and LMO (LIM domain-only) binding protein partners.

Requirement of the Mowat-Wilson Syndrome Gene Zeb2 in the Differentiation and Maintenance of Non-photoreceptor Cell Types During Retinal Development

Mutations in the human transcription factor gene ZEB2 cause Mowat-Wilson syndrome, a congenital disorder characterized by multiple and variable anomalies including microcephaly, Hirschsprung disease, intellectual disability, epilepsy, microphthalmia, retinal coloboma, and/or optic nerve hypoplasia. Zeb2 in mice is involved in patterning neural and lens epithelia, neural tube closure, as well as in the specification, differentiation and migration of neural crest cells and cortical neurons. At present, it is still unclear how Zeb2 mutations cause retinal coloboma, whether Zeb2 inactivation results in retinal degeneration, and whether Zeb2 is sufficient to promote the differentiation of different retinal cell types. Here, we show that during mouse retinal development, Zeb2 is expressed transiently in early retinal progenitors and in all non-photoreceptor cell types including bipolar, amacrine, horizontal, ganglion, and Müller glial cells. Its retina-specific ablation causes severe loss of all non-photoreceptor cell types, cell fate switch to photoreceptors by retinal progenitors, and elevated apoptosis, which lead to age-dependent retinal degeneration, optic nerve hypoplasia, synaptic connection defects, and impaired ERG (electroretinogram) responses. Moreover, overexpression of Zeb2 is sufficient to promote the fate of all non-photoreceptor cell types at the expense of photoreceptors. Together, our data not only suggest that Zeb2 is both necessary and sufficient for the differentiation of non-photoreceptor cell types while simultaneously inhibiting the photoreceptor cell fate by repressing transcription factor genes involved in photoreceptor specification and differentiation, but also reveal a necessity of Zeb2 in the long-term maintenance of retinal cell types. This work helps to decipher the etiology of retinal atrophy associated with Mowat-Wilson syndrome and hence will impact on clinical diagnosis and management of the patients suffering from this syndrome.

Generation of Urine Cell-Derived Non-integrative Human iPSCs and iNSCs: A Step-by-Step Optimized Protocol

Objective: Establishing a practical procedure to generate induced pluripotent stem cells (iPSCs) and induced neural stem cells (iNSCs) from human urine cells (UCs). In this report, we optimized a non-integrative protocol to generate patient-specific iPSC and iNSC lines with high reprogramming efficiency.

Methods: UCs were electroporated with the pEP4-EO2S-ET2K and pEP4-M2L plasmids containing the OCT4, SOX2, KLF4, SV40LT, c-MYC, and LIN28 genes, and then cultured with N2B27 medium plus four small molecule compounds (A83-01, PD0325901, Thiazovivin, and CHIR99021). When iPSC or iNSC clones emerged, the medium was replaced with mTeSR1 or neural growth medium. Morphological changes were seen at day 4–7. After day 10, the clones were picked up when the clone diameter exceeded 1 mm.

Results: iPSCs and iNSCs were successfully derived from UCs with up to 80 clones/well. These iPSCs and iNSCs showed typical hESC or NSC morphology and were self-renewable. The iPSCs had pluripotency to differentiate into the three germinal layers and displayed high levels of expression of pluripotency markers SOX2, NANOG, OCT4, SSEA-4, TRA-1-60, TRA-1-81, and alkaline phosphatase (AP). They maintained normal karyotype and had no transgene expression or genomic integration. The iNSCs were positive for NSC markers NESTIN, PAX6, SOX2, and OLIG2.

Conclusion: The optimized protocol is an easy and fast procedure to yield both iPSC and iNSC lines from a convenient source of human urine in a single experiment.

Hypoxia-Inducible Factor-1α Target Genes Contribute to Retinal Neuroprotection

Hypoxia-inducible factor (HIF) is a transcription factor that facilitates cellular adaptation to hypoxia and ischemia. Long-standing evidence suggests that one isotype of HIF, HIF-1α, is involved in the pathogenesis of various solid tumors and cardiac diseases. However, the role of HIF-1α in retina remains poorly understood. HIF-1α has been recognized as neuroprotective in cerebral ischemia in the past two decades. Additionally, an increasing number of studies has shown that HIF-1α and its target genes contribute to retinal neuroprotection. This review will focus on recent advances in the studies of HIF-1α and its target genes that contribute to retinal neuroprotection. A thorough understanding of the function of HIF-1α and its target genes may lead to identification of novel therapeutic targets for treating degenerative retinal diseases including glaucoma, age-related macular degeneration, diabetic retinopathy, and retinal vein occlusions.

Vsx1 Transiently Defines an Early Intermediate V2 Interneuron Precursor Compartment in the Mouse Developing Spinal Cord

Spinal ventral interneurons regulate the activity of motor neurons, thereby controlling motor activities. Interneurons arise during embryonic development from distinct progenitor domains distributed orderly along the dorso-ventral axis of the neural tube. A single ventral progenitor population named p2 generates at least five V2 interneuron subsets. Whether the diversification of V2 precursors into multiple subsets occurs within the p2 progenitor domain or involves a later compartment of early-born V2 interneurons remains unsolved. Here, we provide evidence that the p2 domain produces an intermediate V2 precursor compartment characterized by the transient expression of the transcriptional repressor Vsx1. These cells display an original repertoire of cellular markers distinct from that of any V2 interneuron population. They have exited the cell cycle but have not initiated neuronal differentiation. They coexpress Vsx1 and Foxn4, suggesting that they can generate the known V2 interneuron populations as well as possible additional V2 subsets. Unlike V2 interneurons, the generation of Vsx1-positive precursors does not depend on the Notch signaling pathway but expression of Vsx1 in these cells requires Pax6. Hence, the p2 progenitor domain generates an intermediate V2 precursor compartment, characterized by the presence of the transcriptional repressor Vsx1, that contributes to V2 interneuron development.

Dynamic landscape of alternative polyadenylation during retinal development

The development of the central nervous system (CNS) is a complex process that must be exquisitely controlled at multiple levels to ensure the production of appropriate types and quantity of neurons. RNA alternative polyadenylation (APA) contributes to transcriptome diversity and gene regulation, and has recently been shown to be widespread in the CNS. However, the previous studies have been primarily focused on the tissue specificity of APA and developmental APA change of whole model organisms; a systematic survey of APA usage is lacking during CNS development. Here, we conducted global analysis of APA during mouse retinal development, and identified stage-specific polyadenylation (pA) sites that are enriched for genes critical for retinal development and visual perception. Moreover, we demonstrated 3'UTR (untranslated region) lengthening and increased usage of intronic pA sites over development that would result in gaining many different RBP (RNA-binding protein) and miRNA target sites. Furthermore, we showed that a considerable number of polyadenylated lncRNAs are co-expressed with protein-coding genes involved in retinal development and functions. Together, our data indicate that APA is highly and dynamically regulated during retinal development and maturation, suggesting that APA may serve as a crucial mechanism of gene regulation underlying the delicate process of CNS development.

Association between the resistin gene-420 C>G polymorphism and obesity: an updated meta-analysis

OBJECTIVE

The aim of this study was to assess the relationship of the resistin gene (RETN)-420 C>G polymorphism and obesity susceptibility by conducting an updated meta-analysis.

MATERIALS AND METHODS

The electronic databases including PubMed, Medline, Embase, China National Knowledge Infrastructure, Chinese Wanfang Database, and Chinese VIP database were searched for relevant studies published before December 2013. The fixed effect model or random effects model was used based on the heterogeneity test results. The sensitivity analysis was performed in the allelic model and the dominant genetic model, respectively. Publication bias was assessed via funnel plot. The meta-analysis was performed using the software of RevMan 5.2.

RESULTS

Data were obtained from 10 included studies, involving 5,069 cases and 6,673 controls. The overall odds ratios (ORs) with its 95% confidence interval (CI) showed no association between RETN-420 C>G polymorphism and obesity in the allelic model (p = 0.09; OR = 1.10; 95% CI = 0.991.24), the dominant model (p = 0.09; OR = 1.16; 95% CI = 0.98-1.36), and the recessive model (p = 0.71; OR = 1.02; 95% CI = 0.90-1.16). Sensitivity analysis showed statistical differences of association analysis within the allelic model (p = 0.04; OR = 1.14; 95% CI = 1.01-1.28) and the dominant genetic model (p = 0.04; OR = 1.21; 95% CI = 1.01-1.45), when 1 study was omitted. No publication bias was observed.

CONCLUSIONS

The RETN-420 C>G polymorphism may be related to obesity with G allele as a risk factor.

Clinic research on the treatment for humeral shaft fracture with minimal invasive plate osteosynthesis: a retrospective study of 128 cases

INTRODUCTION

Minimal invasive plate osteosynthesis (MIPO) is one of the most important techniques in the treatment for humeral shaft fractures. This study was performed to evaluate the efficacy of MIPO technique for the treatment for humeral shaft fractures.

MATERIALS AND METHODS

We retrospectively evaluated 128 cases with humeral shaft fractures that were treated with MIPO technique from March 2005 to August 2008. All the patients were followed up by routine radiological imaging and clinical examinations. Constant-Murley score and HSS elbow joint score were used to evaluate the treatment outcome.

RESULTS

The average duration of the surgery was 60 min (range 40-95 min) without blood transfusion. All fractures healed without infection. All cases recovered carrying angle except four cases with 10°-15° cubitus varus. After the average follow-up of 23 (13-38) months, satisfactory function was achieved according to Constant-Murley score and HSS elbow joint score. Constant-Murley score was 80 on average (range 68-91). According to HSS elbow joint score, there were 123 cases of excellent clinical outcome and five cases of effective outcome.

CONCLUSION

It seems to be a safe and effective method for managing humeral shaft fractures with MIPO technique.

Lmo4 and Other LIM domain only factors are necessary and sufficient for multiple retinal cell type development

Understanding the molecular basis by which distinct cell types are specified is a central issue in retinogenesis and retinal disease development. Here we examined the role of LIM domain only 4 (Lmo4) in retinal development using both gain-of-function and loss-of-function approaches. By immunostaining, Lmo4 was found to be expressed in mouse retina from E10.5 to mature stages. Retroviral delivery of Lmo4 into retinal progenitor cells could promote the amacrine, bipolar and Müller cell fates at the expense of photoreceptors. It also inhibited the fate of early-born retinal ganglion cells. Using a dominant-negative form of Lmo4 which suppresses transcriptional activities of all LIM domain only factors, we demonstrated that LIM domain only factors are both necessary and sufficient for promoting amacrine and bipolar cell development, but not for the differentiation of ganglion, horizontal, Müller, or photoreceptor cells. Taken together, our study uncovers multiple roles of Lmo4 during retinal development and demonstrates the importance of LIM domain only factors in ensuring proper retinal cell specification and differentiation. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 900-915, 2016.

MicroRNAs in avian influenza virus H9N2-infected and non-infected chicken embryo fibroblasts

There is limited information about microRNAs (miR-NAs) in H9N2 subtype influenza virus-infected chicken cells or tissues. In this study, 10,487,469 and 13,119,795 reads were obtained from in-fected and non-infected chicken embryo fibroblasts, respectively. Seven hundred and thirty-six and 1004 miRNAs, including mature miRNAs and precursors, were obtained from the infected and non-infected fibro-blasts, respectively. Of those miRNAs, 48 were expressed differently between the groups: 37 had a low expression level in the infected chick-en embryo fibroblast, and the remaining 11 had a higher expression level. Every miRNA was predicted to target immune response-related genes. It has been found that some of the miRNAs, such as gga-miR-146c, gga-miR-181a, gga-miR-181b, gga-miR-30b, gga-miR-30c, gga-miR-30e, and gga-miR-455, are expressed differently in other types of influenza-infected chicken cells or tissues.

Neurite Mistargeting and Inverse Order of Intraretinal Vascular Plexus Formation Precede Subretinal Vascularization in Vldlr Mutant Mice

In the retina blood vessels are required to support a high metabolic rate, however, uncontrolled vascular growth can lead to impaired vision and blindness. Subretinal vascularization (SRV), one type of pathological vessel growth, occurs in retinal angiomatous proliferation and proliferative macular telangiectasia. In these diseases SRV originates from blood vessels within the retina. We use mice with a targeted disruption in the Vldl-receptor (Vldlr) gene as a model to study SRV with retinal origin. We find that Vldlr mRNA is strongly expressed in the neuroretina, and we observe both vascular and neuronal phenotypes in Vldlr^-/- mice. Unexpectedly, horizontal cell (HC) neurites are mistargeted prior to SRV in this model, and the majority of vascular lesions are associated with mistargeted neurites. In Foxn4^-/- mice, which lack HCs and display reduced amacrine cell (AC) numbers, we find severe defects in intraretinal capillary development. However, SRV is not suppressed in Foxn4^-/-;Vldlr^-/- mice, which reveals that mistargeted HC neurites are not required for vascular lesion formation. In the absence of VLDLR, the intraretinal capillary plexuses form in an inverse order compared to normal development, and subsequent to this early defect, vascular proliferation is increased. We conclude that SRV in the Vldlr^-/- model is associated with mistargeted neurites and that SRV is preceded by altered retinal vascular development.

Psychrophilic fungi from the world's roof

During a survey of cold-adapted fungi in alpine glaciers on the Qinghai-Tibet Plateau, 1 428 fungal isolates were obtained of which 150 species were preliminary identified. Phoma sclerotioides and Pseudogymnoascus pannorum were the most dominant species. Psychrotolerant species in Helotiales (Leotiomycetes, Ascomycota) were studied in more detail as they represented the most commonly encountered group during this investigation. Two phylogenetic trees were constructed based on the partial large subunit nrDNA (LSU) to infer the taxonomic placements of these strains. Our strains nested in two well-supported major clades, which represented Tetracladium and a previously unknown lineage. The unknown lineage is distant to any other currently known genera in Helotiales. Psychrophila gen. nov. was therefore established to accommodate these strains which are characterised by globose or subglobose conidia formed from phialides on short or reduced conidiophores. Our analysis also showed that an LSU-based phylogeny is insufficient in differentiating strains at species level. Additional analyses using combined sequences of ITS+TEF1+TUB regions were employed to further investigate the phylogenetic relationships of these strains. Together with the recognisable morphological distinctions, six new species (i.e. P. antarctica, P. lutea, P. olivacea, T. ellipsoideum, T. globosum and T. psychrophilum) were described. Our preliminary investigation indicates a high diversity of cold-adapted species in nature, and many of them may represent unknown species.

Tfap2a and 2b act downstream of Ptf1a to promote amacrine cell differentiation during retinogenesis

Retinogenesis is a precisely controlled developmental process during which different types of neurons and glial cells are generated under the influence of intrinsic and extrinsic factors. Three transcription factors, Foxn4, RORβ1 and their downstream effector Ptf1a, have been shown to be indispensable intrinsic regulators for the differentiation of amacrine and horizontal cells. At present, however, it is unclear how Ptf1a specifies these two cell fates from competent retinal precursors. Here, through combined bioinformatic, molecular and genetic approaches in mouse retinas, we identify the Tfap2a and Tfap2b transcription factors as two major downstream effectors of Ptf1a. RNA-seq and immunolabeling analyses show that the expression of Tfap2a and 2b transcripts and proteins is dramatically downregulated in the Ptf1a null mutant retina. Their overexpression is capable of promoting the differentiation of glycinergic and GABAergic amacrine cells at the expense of photoreceptors much as misexpressed Ptf1a is, whereas their simultaneous knockdown has the opposite effect. Given the demonstrated requirement for Tfap2a and 2b in horizontal cell differentiation, our study thus defines a Foxn4/RORβ1-Ptf1a-Tfap2a/2b transcriptional regulatory cascade that underlies the competence, specification and differentiation of amacrine and horizontal cells during retinal development.

Selective neuronal lineages derived from Dll4-expressing progenitors/precursors in the retina and spinal cord

BACKGROUND

During retinal and spinal cord neurogenesis, Notch signaling plays crucial roles in regulating proliferation and differentiation of progenitor cells. One of the Notch ligands, Delta-like 4 (Dll4), has been shown to be expressed in subsets of retinal and spinal cord progenitors/precursors and involved in neuronal subtype specification. However, it remains to be determined whether Dll4 expression has any progenitor/precursor-specificity contributing to its functional specificity during neural development.

RESULTS

We generated a Dll4-Cre BAC transgenic mouse line that drives Cre recombinase expression mimicking that of the endogenous Dll4 in the developing retina and spinal cord. By fate-mapping analysis, we found that Dll4-expressing progenitors/precursors give rise to essentially all cone, amacrine and horizontal cells, a large portion of rod and ganglion cells, but only few bipolar and Müller cells. In the spinal cord, Dll4-expressing progenitors/precursors generate almost all V2a and V2c cells while producing only a fraction of the cells for other interneuron and motor neuron subtypes along the dorsoventral axis.

CONCLUSIONS

Our data suggest that selective expression of Dll4 in progenitors/precursors contributes to its functional specificity in neuronal specification and that the Dll4-Cre line is a valuable tool for gene manipulation to study Notch signaling.

Asymmetric activation of Dll4-Notch signaling by Foxn4 and proneural factors activates BMP/TGFβ signaling to specify V2b interneurons in the spinal cord

During development of the ventral spinal cord, the V2 interneurons emerge from p2 progenitors and diversify into two major subtypes, V2a and V2b, that play key roles in locomotor coordination. Dll4-mediated Notch activation in a subset of p2 precursors constitutes the crucial first step towards generating neuronal diversity in this domain. The mechanism behind the asymmetric Notch activation and downstream signaling events are, however, unknown at present. We show here that the Ascl1 and Neurog basic helix-loop-helix (bHLH) proneural factors are expressed in a mosaic pattern in p2 progenitors and that Foxn4 is required for setting and maintaining this expression mosaic. By binding directly to a conserved Dll4 enhancer, Foxn4 and Ascl1 activate Dll4 expression, whereas Neurog proteins prevent this effect, thereby resulting in asymmetric activation of Dll4 expression in V2 precursors expressing different combinations of proneural and Foxn4 transcription factors. Lineage tracing using the Cre-LoxP system reveals selective expression of Dll4 in V2a precursors, whereas Dll4 expression is initially excluded from V2b precursors. We provide evidence that BMP/TGFβ signaling is activated in V2b precursors and that Dll4-mediated Notch signaling is responsible for this activation. Using a gain-of-function approach and by inhibiting BMP/TGFβ signal transduction with pathway antagonists and RNAi knockdown, we further demonstrate that BMP/TGFβ signaling is both necessary and sufficient for V2b fate specification. Our data together thus suggest that the mosaic expression of Foxn4 and proneural factors may serve as the trigger to initiate asymmetric Dll4-Notch and subsequent BMP/TGFβ signaling events required for neuronal diversity in the V2 domain.

Meis1 regulates Foxn4 expression during retinal progenitor cell differentiation

The transcription factor forkhead box N4 (Foxn4) is a key regulator in a variety of biological processes during development. In particular, Foxn4 plays an essential role in the genesis of horizontal and amacrine neurons from neural progenitors in the vertebrate retina. Although the functions of Foxn4 have been well established, the transcriptional regulation of Foxn4 expression during progenitor cell differentiation remains unclear. Here, we report that an evolutionarily conserved 129 bp noncoding DNA fragment (Foxn4CR4.2 or CR4.2), located ∼26 kb upstream of Foxn4 transcription start site, functions as a cis-element for Foxn4 regulation. CR4.2 directs gene expression in Foxn4-positive cells, primarily in progenitors, differentiating horizontal and amacrine cells. We further determined that the gene regulatory activity of CR4.2 is modulated by Meis1 binding motif, which is bound and activated by Meis1 transcription factor. Deletion of the Meis1 binding motif or knockdown of Meis1 expression abolishes the gene regulatory activity of CR4.2. In addition, knockdown of Meis1 expression diminishes the endogenous Foxn4 expression and affects cell lineage development. Together, we demonstrate that CR4.2 and its interacting Meis1 transcription factor play important roles in regulating Foxn4 expression during early retinogenesis. These findings provide new insights into molecular mechanisms that govern gene regulation in retinal progenitors and specific cell lineage development.

Onecut1 is essential for horizontal cell genesis and retinal integrity

Horizontal cells are interneurons that synapse with photoreceptors in the outer retina. Their genesis during development is subject to regulation by transcription factors in a hierarchical manner. Previously, we showed that Onecut 1 (Oc1), an atypical homeodomain transcription factor, is expressed in developing horizontal cells (HCs) and retinal ganglion cells (RGCs) in the mouse retina. Herein, by knocking out Oc1 specifically in the developing retina, we show that the majority (∼80%) of HCs fail to form during early retinal development, implying that Oc1 is essential for HC genesis. However, no other retinal cell types, including RGCs, were affected in the Oc1 knock-out. Analysis of the genetic relationship between Oc1 and other transcription factor genes required for HC development revealed that Oc1 functions downstream of FoxN4, in parallel with Ptf1a, but upstream of Lim1 and Prox1. By in utero electroporation, we found that Oc1 and Ptf1a together are not only essential, but also sufficient for determination of HC fate. In addition, the synaptic connections in the outer plexiform layer are defective in Oc1-null mice, and photoreceptors undergo age-dependent degeneration, indicating that HCs are not only an integral part of the retinal circuitry, but also are essential for the survival of photoreceptors. In sum, these results demonstrate that Oc1 is a critical determinant of HC fate, and reveal that HCs are essential for photoreceptor viability, retinal integrity, and normal visual function.