4 ADDITIONAL MEMBERS OF THE RAS GENE SUPERFAMILY ISOLATED BY AN OLIGONUCLEOTIDE STRATEGY - MOLECULAR-CLONING OF YPT-RELATED CDNAS FROM A RAT-BRAIN LIBRARY
4 ADDITIONAL MEMBERS OF THE RAS GENE SUPERFAMILY ISOLATED BY AN OLIGONUCLEOTIDE STRATEGY - MOLECULAR-CLONING OF YPT-RELATED CDNAS FROM A RAT-BRAIN LIBRARY
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DOI：
10.1073/pnas.84.23.8210
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发表时间：
1987-12-01
影响因子：
11.1
通讯作者：
TAVITIAN, A
中科院分区：
文献类型：
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作者：
TOUCHOT, N;CHARDIN, P;TAVITIAN, A
几种寡核苷酸混合物对应的6个氨基酸序列，是严格保守的所有ras和ras相关的蛋白质（从各种生物）进行了测试，其杂交能力的ras基因超家族的11个克隆成员。在这些混合物中，两组部分互补寡聚体的组合能够与所有测试序列杂交。为了识别ras超家族的成员，我们用这些探针筛选了大鼠脑cDNA文库，并分离出4个基因，表示为rab 1，-2，-3和-4，编码与酵母YPT蛋白同源的蛋白质。与YPT的氨基酸同源性得分范围从rab 1的75%到rab 4的37%，而与p21 ras和其它ras相关蛋白的同源性为约30%，并且同源残基聚集在涉及GTP/GDP结合的区域中。rab和其他ras相关蛋白的另一个惊人的相似之处是保守的羧基末端附近的至少一个半胱氨酸残基参与ras蛋白的膜结合。rab 1是酵母YPT基因的哺乳动物同源物，并且四个rab基因构成ras基因超家族的额外分支，据我们所知，其尚未在高等真核生物中描述。
Several oligonucleotide mixtures corresponding to a 6-amino acid sequence that is strictly conserved in all the ras and ras-related proteins (from various organisms) were tested for their ability to hybridize to 11 cloned members of the ras gene superfamily. Among these mixtures, a combination of two sets of partially complementary oligomers were able to hybridize to all the tested sequences. To identify members of the ras superfamily, we screened a rat brain cDNA library with these probes and isolated four genes, denoted rab1, -2, -3, and -4, encoding proteins homologous to the yeast YPT protein. Amino acid homology scores with YPT range from 75% for rab1 to 37% for rab4, whereas the homologies with p21 ras and othr ras-related proteins are .apprxeq.30%, and homologous residues were clustered in the regions involved in GTP/GDP binding. Another striking similarity shared by the rab and the other ras-related proteins is the conservation of at least one cysteine residue near the carboxyl-terminal end involved in the membrane binding of the ras proteins. rab1 is a mammalian homolog of the yeast YPT gene, and the four rab genes constitute an additional branch of the ras gene superfamily that to our knowledge has not been described in higher eukaryotes.