Two members of the human testis-specific serine/threonine (Ser/Thr) kinase family, TSSK 1 and TSSK 2, were cloned and sequenced from a human testis adaptor-ligated cDNA library using a PCR strategy. Within the cDNA, open reading frames (ORF) were defined encoding proteins of 367 and 358 amino acids respectively, as well as conserved kinase domains typical of the superfamily of Ser/Thr kinases. Both genes were intronless and mapped to chromosomes 5 and 22 respectively. The human and mouse homologues of TSSK 1 and TSSK 2, together with TSSK 3 and SSTK/FKSG82, constitute a kinase subfamily closely related to the calmodulin kinases and SNF/nim 1 kinase subfamilies. Similar to the mouse, tissue expression by northern and dot blot analysis revealed that human TSSK 1 and 2 messages are expressed exclusively in the testis. However, mRNA for these kinases can be detected in other tissues using real-time PCR. In addition, TSKS, the human homologue of a putative substrate of TSSK 1 and 2, was cloned. TSKS had an ORF of 592 amino acids and was also expressed exclusively in the testis as demonstrated by northern and dot blot analyses; however, lower levels of expression in other tissues were detected using real-time PCR. Human TSSK 2 and TSKS interacted in a yeast two-hybrid system and also co-immunoprecipitated after in vitro translation. TSSK 2 expressed in yeast and bacteria was able to autophosphorylate and also phosphorylated recombinant TSKS in vitro. Antibodies against recombinant TSSK 2 demonstrated that a member of the TSSK family was present in human testis and localized to the equatorial segment of ejaculated human sperm. In contrast, TSKS was only found in the testis. The finding of a TSSK family member in mature sperm suggests that this family of kinases might play a role in sperm function.
SpermCheck Fertility is a simple and reliable immunodiagnostic test that can quickly inform men as to whether their sperm count is normal, low or very low. This home test can assist couples in deciding whether to seek comprehensive clinical evaluation of the fertility status of the male partner.
We determined the phenotype and genotype of murine leukemia viruses associated with the development of spontaneous nonthymic lymphomas in the high-leukemia mouse strain CWD/J. By T, oligonucleotide fingerprint analysis of the viral RNA, the ecotropic viruses recovered from the spleen or thymus of preleukemic CWD/J mice were found to represent the progeny of the two endogenous ecotropic proviruses present in this strain. Polytropic murine leukemia viruses were produced by tissues from one-half of the leukemic mice, and fresh tumor cells from one of the two animals tested expressed recombinant envelope glycoproteins. The genomic structure of the recombinant viruses resembled those of class II polytropic viruses of NFS * Akv mice and differed from those of class I recombinant viruses that are commonly isolated from other high-leukemia strains such as AKR and HRS. Acquired retroviral sequences with the structural features of class II recombinant proviruses were detected in the DNA from each CWD/J tumor by the Southern blot technique. Finally, the injection of a mixture of CWD/J ecotropic and class II recombinant polytropic viruses into neonatal CWD/J mice accelerated the onset of lymphoma, whereas the endogenous ecotropic virus was inactive in these assays.
Multiple isoforms (TAG-1, TAG-2a, TAG-2b, and TAG-2c) of a novel cancer/testis antigen gene have been identified and are expressed in 84 -88% of melanoma cell lines tested. The tumor antigen (TAG) genes are also expressed in K562, a myelogenous leukemia cell line, and they have homology to two chronic myelogenous leukemia-derived clones and a hepatocellular carcinoma clone in the human expressed sequence tags (EST) database, thus indicating that their expression is not restricted to melanomas. In contrast to the fact that many cancer/testis antigens are poorly immunogenic, the TAG-derived peptide, RLSNRLLLR, is recognized by HLA-A3-restricted, melanoma-specific CTLs that were obtained from a melanoma patient with spontaneous reactivity to the peptide. Unlike most cancer/testis antigen genes which are located on the X chromosome, the TAG genes are located on chromosome 5. The genes have the additional unusual features of being coded for in an open reading frame that is initiated by one of three nonstandard initiation codons, and the sequence coding the RLSNRLLLR peptide crosses an exon-exon boundary. The properties of the TAG antigens indicate that they are excellent vaccine candidates for the treatment of melanoma and perhaps other cancers.
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