[Cloning of human B lymphocyte activation-related novel gene].

OBJECTIVE: To clone the novel activation-related gene of B lymphocyte. METHODS: The differential display reversal transcription PCR (DDRT-PCR) technique was applied to analyse the expression difference of mRNA between resting and activated B lymphocyte from human tonsil. The positive differential display cDNA fragment identified by Northern-blotting was chosen as probe to filtrate human activated B lymphocyte cDNA library. RESULTS: Sixty two differential display cDNA fragments (expressed sequence tag, EST) were obtained. Thirty-two of them were mainly expressed in resting B lymphocyte and thirty were expressed in activated cells. Twenty-five were positive ones after identification by Northern blot analysis. A novel cDNA clone was obtained after using EST30 as a probe to filtrate the human activated B cell cDNA library. The whole cDNA clone was 2,048 bp in length and contains a 630 bp open reading frame. The N end of the deduced amino acid sequence was homologous with KAR3 protein which is a member of kinesins superfamily in yeast. CONCLUSIONS: A novel possible activation-related gene in human B lymphocyte was obtained.