关键词：
日本百脉根;γ-生育酚甲基转移酶;电子克隆;EST
摘 要：
根据物种间同源基因相对保守的特点,利用生物信息学方法,以拟南芥-γ生育酚甲基转移酶cDNA序列为信息探针,在GenBank的HTGs数据库中找到与之高度同源的日本百脉根基因组DNA序列——LjT44D21克隆。通过GENSCAN分析及序列拼接得到日本百脉根"γTMT基因的cDNA序列,GenBank的登陆号为DQ013360。用该序列对GenBank中的est-others进行相似性搜索,获得了44条日本百脉根的EST序列,经拼接后发现与基因组预测的基因序列一致,表明该基因是真实存在和表达的。该cDNA序列长为1 077 bp,具有完整的开放阅读框架(1～1 077 bp)。推测编码蛋白为358个氨基酸,该蛋白序列与大豆、水稻、小麦、拟南芥、油菜、苜蓿和衣藻等物种的-γTMT蛋白质序列进行了同源性比较分析,具有很高的同源性。
译 名：
In silico Cloning of Gamma-tocopherol Methyltransferase Gene from Lotus corniculatus var.japonicus
作 者：
MENG Xian-ping et al(College of Life Science,Capital Normal University,Beijing 100037)
关键词：
Lotus corniculatus var.japonicus;γ-TMT;in silico cloning;EST
摘 要：
In silico cloning is a new method for gene cloning.Arabidopsis thialiana γ-TMT cDNA sequence(GenBank accession number AY090280) being used as a querying probe to BLAST the HTGs database,a highly homologous DNA sequence,which was referred as LjT44D21clone,was obtained.After performing the GENSCAN program,a positive gene,which comprised of 6 exons and 5 introns,was found.With the predicted sequence to BLAST GenBank est-others database,44 ESTs homologous sequences hit can be edited to a unique sequence which was the same as the predicted sequence from genomic DNA.These results showed that this gene authentically existed and expressed.This 1 077 bp gene contained a complete ORF(1 bp-1 077 bp),encoded 358 amino acids,which was very conserved with Glycine max,Oryza sative,Triticum aestivum,Arabidopsis thaliana,Brassica oleracea,Medicago truncatula and Chlamydomonas reinhardtii,respectively.
