Assignment of the human homologue of the mouse t-complex gene TCTE3 to human chromosome 6q27

Disruption of murine Tcte3-3 induces tissue specific apoptosis via co-expression of Anxa5 and Pebp1

Programmed cell death or apoptosis plays a vital physiological role in the development and homeostasis. Any discrepancy in apoptosis may trigger testicular and neurodegenerative diseases, ischemic damage, autoimmune disorders and many types of cancer. Tcte3 (T-complex testis expressed 3) is an accessory component of axonemal and cytoplasmic dynein which expresses predominantly in meiotic and postmeiotic germ cells. It plays an essential role during spermatogenesis; however, to explore its diverse and complex functioning in male germ cell apoptosis, requires further prosecution. Here, 2D-gel electrophoresis, mass spectrometry and qRT-PCR analyses were performed to elucidate the differential expression of genes, in both wild-type and homozygous Tcte3-3 mice. We observed an increased expression of Tcte3 in homozygotes as compared to wild-type testes. Perpetually, an increased expression of Anxa5 and Pebp1, while a lower expression of Rsph1 was detected in Tcte3-3^-/- mice. We propose that over-expression of Pebp1 and Anxa5 in Tcte3-3^-/- testes might be due to increased apoptosis. To evaluate this possibility, testes specific microarray data set extracted from NCBI gene ontology omnibus (GEO) was used to cluster the possible co-expression partners of Tcte3. Further functional coherence of compiled candidate genes was monitored computationally by studying the common TFBS overlapped at the regulatory regions. Differential expression of Tcte3-3 and its involvement in apoptosis may provide a basis for the investigation of transcriptional specificities of other Tcte3 paralogs (Tcte3-1 and Tcte3-2). A complete understanding of controlling factors which have implications in regulating tissue-specific Tcte3 expression would provide additional insights into the gene control events. The collective knowledge may prove useful for the development of novel therapeutic regimen and would open new avenues in defining selective roles of Tcte3 in germ cell development.

Genetic analysis of the cytoplasmic dynein subunit families

Cytoplasmic dyneins, the principal microtubule minus-end-directed motor proteins of the cell, are involved in many essential cellular processes. The major form of this enzyme is a complex of at least six protein subunits, and in mammals all but one of the subunits are encoded by at least two genes. Here we review current knowledge concerning the subunits, their interactions, and their functional roles as derived from biochemical and genetic analyses. We also carried out extensive database searches to look for new genes and to clarify anomalies in the databases. Our analysis documents evolutionary relationships among the dynein subunits of mammals and other model organisms, and sheds new light on the role of this diverse group of proteins, highlighting the existence of two cytoplasmic dynein complexes with distinct cellular roles.

The human homolog T of the mouse T(Brachyury) gene; gene structure, cDNA sequence, and assignment to chromosome 6q27

We have cloned the human gene encoding the transcription factor T. T protein is vital for the formation of posterior mesoderm and axial development in all vertebrates. Brachyury mutant mice, which lack T protein, die in utero with abnormal notochord, posterior somites, and allantois. We have identified human T genomic clones and derived the mRNA sequence and gene structure. There is 91% amino acid identity between human and mouse T proteins overall and complete identity across 77 amino acids of the T-box motif within the DNA-binding domain. Human T expression is very similar to that found for T in other vertebrate species and is confined to cells derived from the notochord. The human T gene maps to chromosome 6q27 and is only the second human member of the T-box gene family to be described.

Human leukocyte antigen DQ alpha sharing is not increased in couples with recurrent miscarriage

PROBLEM

The results regarding human leukocyte antigen (HLA) DQ alpha allele sharing in recurrent miscarriage couples are conflicting. The purpose of this study was to determine the frequency of HLA DQ alpha allele sharing in our unexplained recurrent spontaneous abortion (RSA) patients using modern DNA analytical techniques.

METHODS

DNA was extracted from whole blood samples of 1) 51 couples with at least three miscarriages, and 2) 43 fertile couples (with at least seven children and no known history of recurrent miscarriage). The polymerase chain reaction (PCR) was used to amplify the second exon of the HLA DQ alpha locus on chromosome 6. Genotypes were identified by allele specific hybridization with 12 sequence-specific oligonucleotide probes.

RESULTS

47% of recurrent miscarriage couples and 35% of fertile couples shared no alleles. 47% of recurrent miscarriage couples compared to 58% of fertile couples shared one allele, and 6% of recurrent miscarriage couples and 7% of fertile couples shared two alleles.

CONCLUSIONS

Reproductive partners with unexplained recurrent pregnancy loss have no increased frequency of HLA DQ alpha allele sharing. It is unlikely that HLA DQ alpha genotyping will be helpful in the management of patients with RSA.