Indian Red Jungle fowl reveals a genetic relationship with South East Asian Red Jungle fowl and Indian native chicken breeds as evidenced through whole mitochondrial genome sequences

Background: Native chickens are dispersed in a wide geographical range and have hereditary assets that are kept by farmers for various purposes. Mitochondrial DNA (mtDNA) is a widely utilized marker in molecular studies because of its quick advancement, matrilineal legacy, and simple molecular structure. Method and Results: We performed NGS sequencing to investigate mitochondrial genomes and to evaluate the hereditary connections, diversity, and measure of gene stream estimation in Indian native chicken breeds and Red Jungle fowl. The chicken breeds were genotyped using the D-loop region and 23 haplotypes were identified. When compared to Indian native breeds, more haplotypes were identified in the NADH dehydrogenase subunits, Cytochrome c oxidase, Cytochrome b, ATP synthase subunit 6, and Ribosomal RNA genes. The phylogenetic examination indicated that the analyzed chicken breeds were divided into six significant clades, namely A, B, C, D, E, and F, of which the F clade indicated the domestication of chicken breeds in India. Additionally, our work affirmed that the Indian Red Jungle Fowl is the origin for both reference Red Jungle Fowl as well as all Indian breeds, which is reflected in the dendrogram as well as network analysis based on the whole mtDNA and D-loop region. Indian Red Jungle Fowl is distributed as an outgroup, suggesting that this ancestry was reciprocally monophyletic. Conclusion: The mtDNA sequences of Indian native chickens provided novel insights into adaptation mechanisms and the significance of important mtDNA variations in understanding the maternal lineages of native birds.

Embryonic transcriptome unravels mechanisms and pathways underlying embryonic development with respect to muscle growth, egg production, and plumage formation in native and broiler chickens

Background: Muscle development, egg production, and plumage colors are different between native and broiler chickens. The study was designed to investigate why improved Aseel (PD4) is colorful, stronger, and grew slowly compared with the control broiler (CB).

Methods: A microarray was conducted using the 7th-day embryo (7EB) and 18th-day thigh muscle (18TM) of improved Aseel and broiler, respectively. Also, we have selected 24 Gallus gallus candidate reference genes from NCBI, and total RNA was isolated from the broiler, improved Aseel embryo tissues, and their expression profiles were studied by real-time quantitative PCR (qPCR). Furthermore, microarray data were validated with qPCR using improved Aseel and broiler embryo tissues.

Results: In the differential transcripts screening, all the transcripts obtained by microarray of slow and fast growth groups were screened by fold change ≥ 1 and false discovery rate (FDR) ≤ 0.05. In total, 8,069 transcripts were differentially expressed between the 7EB and 18TM of PD4 compared to the CB. A further analysis showed that a high number of transcripts are differentially regulated in the 7EB of PD4 (6,896) and fewer transcripts are differentially regulated (1,173) in the 18TM of PD4 compared to the CB. On the 7th^- and 18th-day PD4 embryos, 3,890, 3,006, 745, and 428 transcripts were up- and downregulated, respectively. The commonly up- and downregulated transcripts are 91 and 44 between the 7th- and 18th-day of embryos. In addition, the best housekeeping gene was identified. Furthermore, we validated the differentially expressed genes (DEGs) related to muscle growth, myostatin signaling and development, and fatty acid metabolism genes in PD4 and CB embryo tissues by qPCR, and the results correlated with microarray expression data.

Conclusion: Our study identified DEGs that regulate the myostatin signaling and differentiation pathway; glycolysis and gluconeogenesis; fatty acid metabolism; Jak-STAT, mTOR, and TGF-β signaling pathways; tryptophan metabolism; and PI3K-Akt signaling pathways in PD4. The results revealed that the gene expression architecture is present in the improved Aseel exhibiting embryo growth that will help improve muscle development, differentiation, egg production, protein synthesis, and plumage formation in PD4 native chickens. Our findings may be used as a model for improving the growth in Aseel as well as optimizing the growth in the broiler.

Transcript profiling of genes expressed during fibre development in diploid cotton (Gossypium arboreum L.)

Background

Cotton fibre is a single cell and it is one of the best platforms for unraveling the genes express during various stages of fibre development. There are reports devoted to comparative transcriptome study on fiber cell initiation and elongation in tetraploid cultivated cotton. However, in the present investigation, comparative transcriptome study was made in diploid cultivated cotton using isogenic fuzzy-lintless (Fl) and normal fuzzy linted (FL) lines belong to Gossypium arboreum, diploid species at two stages, 0 and 10 dpa (days post anthesis), using Affymetrix cotton GeneChip genome array.

Result

Scanning electron microscopy (SEM) analysis uncovered the occurrence of few fibre cell initials in the Fl line as compared to many in Normal FL at −2 and 0 dpa. However, at 10 dpa there were no fibre cells found elongated in Fl but many elongated cells were found in FL line. Up-regulation of transcription factors, AP2-EREBP, C2H2, C3H, HB and WRKY was observed at 0 dpa whereas in 10 dpa transcription factors, AP2-EREBP, AUX/IAA, bHLH, C2H2, C3H, HB, MYB, NAC, Orphans, PLATZ and WRKY were found down regulated in Fl line. These transcription factors were mainly involved in metabolic pathways such as phytohormone signaling, energy metabolism of cell, fatty acid metabolism, secondary metabolism and other signaling pathways and are related directly or indirectly in fiber development. Quantitative real-time PCR was performed to check fold up or down-regulation of these genes and transcription factors (TFs) down regulated in mutants as compared to normal at 0 and 10 dpa.

Conclusion

This study elucidates that the up-regulation of transcription factors like AP2-EREBP, C2H2, C3H, HB, WRKY and phytohormone signaling genes at 0 dpa and their down-regulation at the 10 dpa might have constrain the fibre elongation in fuzzy-lintless line. Along with this the down-regulation of genes involved in synthesis of VLCFA chain, transcripts necessary for energy and cell wall metabolism, EXPANSINs, arabinogalactan proteins (AGPs), tubulin might also be the probable reason for reduced growth of fibres in the Fl. Plant receptor-like kinases (RLKs), Leucine Rich Repeats) LRR- family protein and signal transduction coding for mitogen-activated protein kinase (MAPK) cascade, have been engaged in coordination of cell elongation and SCW biosynthesis, down-regulation of these might loss the function leads to reduced fibre growth.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-4066-y) contains supplementary material, which is available to authorized users.

Genome-wide transcriptomic and proteomic analyses of bollworm-infested developing cotton bolls revealed the genes and pathways involved in the insect pest defence mechanism

Cotton bollworm, Helicoverpa armigera, is a major insect pest that feeds on cotton bolls causing extensive damage leading to crop and productivity loss. In spite of such a major impact, cotton plant response to bollworm infection is yet to be witnessed. In this context, we have studied the genome-wide response of cotton bolls infested with bollworm using transcriptomic and proteomic approaches. Further, we have validated this data using semi-quantitative real-time PCR. Comparative analyses have revealed that 39% of the transcriptome and 35% of the proteome were differentially regulated during bollworm infestation. Around 36% of significantly regulated transcripts and 45% of differentially expressed proteins were found to be involved in signalling followed by redox regulation. Further analysis showed that defence-related stress hormones and their lipid precursors, transcription factors, signalling molecules, etc. were stimulated, whereas the growth-related counterparts were suppressed during bollworm infestation. Around 26% of the significantly up-regulated proteins were defence molecules, while >50% of the significantly down-regulated were related to photosynthesis and growth. Interestingly, the biosynthesis genes for synergistically regulated jasmonate, ethylene and suppressors of the antagonistic factor salicylate were found to be up-regulated, suggesting a choice among stress-responsive phytohormone regulation. Manual curation of the enzymes and TFs highlighted the components of retrograde signalling pathways. Our data suggest that a selective regulatory mechanism directs the reallocation of metabolic resources favouring defence over growth under bollworm infestation and these insights could be exploited to develop bollworm-resistant cotton varieties.

GhDRIN1, a novel drought-induced gene of upland cotton (Gossypium hirsutum L.) confers abiotic and biotic stress tolerance in transgenic tobacco

A novel stress tolerance cDNA fragment encoding GhDRIN1 protein was identified and its regulation was studied in cotton boll tissues and seedlings subjected to various biotic and abiotic stresses. Phylogenetic and conserved domain prediction indicated that GhDRIN1 was annotated with a hypothetical protein of unknown function. Subcellular localization showed that GhDRIN1 is localized in the chloroplasts. The promoter sequence was isolated and subjected to in silico study. Various cis-acting elements responsive to biotic and abiotic stresses and hormones were found. Transgenic tobacco seedlings exhibited better growth on amended MS medium and showed minimal leaf damage in insect bioassays carried out with Helicoverpa armigera larvae. Transgenic tobacco showed better tolerance to water-deficit and fast recovered upon rewatering. Present work demonstrated that GhDRIN1, a novel stress tolerance gene of cotton, positively regulates the response to biotic and abiotic stresses in transgenic tobacco.

Glycoproteome of elongating cotton fiber cells

Cotton ovule epidermal cell differentiation into long fibers primarily depends on wall-oriented processes such as loosening, elongation, remodeling, and maturation. Such processes are governed by cell wall bound structural proteins and interacting carbohydrate active enzymes. Glycosylation plays a major role in the structural, functional, and localization aspects of the cell wall and extracellular destined proteins. Elucidating the glycoproteome of fiber cells would reflect its wall composition as well as compartmental requirement, which must be system specific. Following complementary proteomic approaches, we have identified 334 unique proteins comprising structural and regulatory families. Glycopeptide-based enrichment followed by deglycosylation with PNGase F and A revealed 92 unique peptides containing 106 formerly N-linked glycosylated sites from 67 unique proteins. Our results showed that structural proteins like arabinogalactans and carbohydrate active enzymes were relatively more abundant and showed stage- and isoform-specific expression patterns in the differentiating fiber cell. Furthermore, our data also revealed the presence of heterogeneous and novel forms of structural and regulatory glycoproteins. Comparative analysis with other plant glycoproteomes highlighted the unique composition of the fiber glycoproteome. The present study provides the first insight into the identity, abundance, diversity, and composition of the glycoproteome within single celled cotton fibers. The elucidated composition also indirectly provides clues about unicellular compartmental requirements underlying single cell differentiation.

Functional genomics of fuzzless-lintless mutant of Gossypium hirsutum L. cv. MCU5 reveal key genes and pathways involved in cotton fibre initiation and elongation

Background

Fuzzless-lintless cotton mutants are considered to be the ideal material to understand the molecular mechanisms involved in fibre cell development. Although there are few reports on transcriptome and proteome analyses in cotton at fibre initiation and elongation stages, there is no comprehensive comparative transcriptome analysis of fibre-bearing and fuzzless-lintless cotton ovules covering fibre initiation to secondary cell wall (SCW) synthesis stages. In the present study, a comparative transcriptome analysis was carried out using G. hirsutum L. cv. MCU5 wild-type (WT) and it’s near isogenic fuzzless-lintless (fl) mutant at fibre initiation (0 dpa/days post anthesis), elongation (5, 10 and 15 dpa) and SCW synthesis (20 dpa) stages.

Results

Scanning electron microscopy study revealed the delay in the initiation of fibre cells and lack of any further development after 2 dpa in the fl mutant. Transcriptome analysis showed major down regulation of transcripts (90%) at fibre initiation and early elongation (5 dpa) stages in the fl mutant. Majority of the down regulated transcripts at fibre initiation stage in the fl mutant represent calcium and phytohormone mediated signal transduction pathways, biosynthesis of auxin and ethylene and stress responsive transcription factors (TFs). Further, transcripts involved in carbohydrate and lipid metabolisms, mitochondrial electron transport system (mETS) and cell wall loosening and elongation were highly down-regulated at fibre elongation stage (5–15 dpa) in the fl mutant. In addition, cellulose synthases and sucrose synthase C were down-regulated at SCW biosynthesis stage (15–20 dpa). Interestingly, some of the transcripts (~50%) involved in phytohormone signalling and stress responsive transcription factors that were up-regulated at fibre initiation stage in the WT were found to be up-regulated at much later stage (15 dpa) in fl mutant.

Conclusions

Comparative transcriptome analysis of WT and its near isogenic fl mutant revealed key genes and pathways involved at various stages of fibre development. Our data implicated the significant role of mitochondria mediated energy metabolism during fibre elongation process. The delayed expression of genes involved in phytohormone signalling and stress responsive TFs in the fl mutant suggests the need for a coordinated expression of regulatory mechanisms in fibre cell initiation and differentiation.

Genome-wide transcriptomic analysis of cotton under drought stress reveal significant down-regulation of genes and pathways involved in fibre elongation and up-regulation of defense responsive genes

Cotton is an important source of natural fibre used in the textile industry and the productivity of the crop is adversely affected by drought stress. High throughput transcriptomic analyses were used to identify genes involved in fibre development. However, not much information is available on cotton genome response in developing fibres under drought stress. In the present study a genome wide transcriptome analysis was carried out to identify differentially expressed genes at various stages of fibre growth under drought stress. Our study identified a number of genes differentially expressed during fibre elongation as compared to other stages. High level up-regulation of genes encoding for enzymes involved in pectin modification and cytoskeleton proteins was observed at fibre initiation stage. While a large number of genes encoding transcription factors (AP2-EREBP, WRKY, NAC and C2H2), osmoprotectants, ion transporters and heat shock proteins and pathways involved in hormone (ABA, ethylene and JA) biosynthesis and signal transduction were up-regulated and genes involved in phenylpropanoid and flavonoid biosynthesis, pentose and glucuronate interconversions and starch and sucrose metabolism pathways were down-regulated during fibre elongation. This study showed that drought has relatively less impact on fibre initiation but has profound effect on fibre elongation by down-regulating important genes involved in cell wall loosening and expansion process. The comprehensive transcriptome analysis under drought stress has provided valuable information on differentially expressed genes and pathways during fibre development that will be useful in developing drought tolerant cotton cultivars without compromising fibre quality.

Genome-wide transcriptome and proteome analyses of tobacco psaA and psbA deletion mutants

Photosynthesis in higher land plants is a complex process involving several proteins encoded by both nuclear and chloroplast genomes that require a highly coordinated gene expression. Significant changes in plastid differentiation and biochemical processes are associated with the deletion of chloroplast genes. In this study we report the genome-wide responses caused by the deletion of tobacco psaA and psbA genes coding core components of photosystem I (PSI) and photosystem II (PSII), respectively, generated through a chloroplast genetic engineering approach. Transcriptomic and quantitative proteomic analysis showed the down regulation of specific groups of nuclear and chloroplast genes involved in photosynthesis, energy metabolism and chloroplast biogenesis. Moreover, our data show simultaneous activation of several defense and stress responsive genes including those involved in reactive oxygen species (ROS) scavenging mechanisms. A major finding is the differential transcription of the plastome of deletion mutants: genes known to be transcribed by the plastid encoded polymerase (PEP) were generally down regulated while those transcribed by the nuclear encoded polymerase (NEP) were up regulated, indicating simultaneous activation of multiple signaling pathways in response to disruption of PSI and PSII complexes. The genome wide transcriptomic and proteomic analysis of the ∆psaA and ∆psbA deletion mutants revealed a simultaneous up and down regulation of the specific groups of genes located in nucleus and chloroplasts suggesting a complex circuitry involving both retrograde and anterograde signaling mechanisms responsible for the coordinated expression of nuclear and chloroplast genomes.