title: Presence of alternative 5' untranslated sequences and identification of cells expressing ctk transcripts in the brain and testis.
abstract: From a mouse brain cDNA library, two species of the Csk-type tyrosine kinase (ctk) gene containing different 5' untranslated sequences were cloned. Using the common as well as specific nucleotide sequences of the two clones as probes, we examined the expression of ctk in various mouse tissues by Northern blot analysis. The results indicated that both species of ctk were expressed in the brain, testis and bone marrow. By in situ histochemistry of the brain, ctk transcript was detected in neurons throughout the entire brain, especially those of the cortex, the hippocampus and the cerebellum. This distribution pattern is similar to that of the Src family kinases including Yes, Src, Fyn and Lyn. In the testis, the major transcript (0.7 kb) was shorter than that expressed in the brain and the bone marrow (2.0 kb). A subsequent Northern blot analysis of fractionated germ cell populations and in situ histochemistry revealed that the short and long transcripts were expressed in germ cells and somatic cells, respectively, and that the expression level was quantitatively regulated during germ cell development. These results suggest that Ctk is involved in the regulation of neural function and differentiation of male germ cells through interactions with member(s) of the Src family kinases.
authors.affiliation: Department of Clinical Molecular Biology, Faculty of Medicine, Kyoto University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kaneko
authors.forename: K
authors.initials: K
authors.lastname: Nonoguchi
authors.forename: H
authors.initials: H
authors.lastname: Fukuyama
authors.forename: S
authors.initials: S
authors.lastname: Takano
authors.forename: H
authors.initials: H
authors.lastname: Higashitsuji
authors.forename: H
authors.initials: H
authors.lastname: Nishiyama
authors.forename: J
authors.initials: J
authors.lastname: Takenawa
authors.forename: H
authors.initials: H
authors.lastname: Nakayama
authors.forename: J
authors.initials: J
authors.lastname: Fujita
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D001921:Brain / Q000378:metabolism*; D018076:DNA, Complementary / Q000302:isolation & purification; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D016392:Proto-Oncogene Proteins pp60(c-src); D012333:RNA, Messenger / Q000032:analysis*; D013737:Testis / Q000378:metabolism*
chemical_list: D018076:DNA, Complementary; D012333:RNA, Messenger; C086603:Matk protein, mouse; D011505:Protein-Tyrosine Kinases; D016392:Proto-Oncogene Proteins pp60(c-src)