Developmental regulation and neuronal expression of the mRNA of rat n-chimaerin, a p21rac GAP:cDNA sequence.
Developmental regulation and neuronal expression of the mRNA of rat n-chimaerin, a p21rac GAP:cDNA sequence.
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大鼠 n-chimaerin（p21rac GAP：cDNA 序列）mRNA 的发育调节和神经元表达。
作者：
Hong Hwa Lim;G. Michael;P. Smith;L. Lim;Christine Hall
人n-chimaerin是p21 rac和佛波酯受体的GTP酶激活蛋白（GAP）。我们已经分离出大鼠的N-嵌合蛋白的cDNA和研究在大脑中的mRNA表达的细胞和发育模式。在编码区和3 '-非翻译区（UTR）的前400个核苷酸中与人n-嵌合蛋白存在广泛的序列保守性（分别为90%和83%的同一性）。与已报道的人cDNA相比，大鼠cDNA编码额外的35个N-末端氨基酸，其具有5 '-UTR序列倒位和41个核苷酸的缺失，包括推定的起始蛋氨酸。大鼠cDNA编码334个氨基酸的蛋白质（38200 M（r），pI 8.04），在校正人5 '-DNA序列后，与人蛋白质具有97%的氨基酸序列同一性。n-Chimaerin mRNA在胚胎大鼠脑中在15天检测到，并且从出生到20天的出生后数量增加，与细胞分化和突触发生一致。n-Chimaerin mRNA仅限于神经元，在海马锥体细胞、齿状回颗粒细胞和皮质神经元中浓度最高。在小脑中，仅在浦肯野神经元中检测到mRNA。mRNA表达的模式和特异性表明，N-嵌合蛋白在神经元信号转导机制中发挥重要作用。
Human n-chimaerin is a GTPase-activating protein (GAP) for p21rac and a phorbol ester receptor. We have isolated rat n-chimaerin cDNA and investigated the cellular and developmental pattern of mRNA expression in the brain. There is extensive sequence conservation with human n-chimaerin in the coding region and the first 400 nucleotides of the 3'-untranslated region (UTR) (90% and 83% identity respectively). The rat cDNA encodes an additional 35 N-terminal amino acids compared with the reported human cDNA, which has a 5'-UTR sequence inversion and a 41-nucleotide deletion including the putative initiator methionine. The rat cDNA encodes a 334-amino acid protein (38200 M(r), pI 8.04) with 97% amino acid sequence identity with the human protein, after correction of the human 5'-DNA sequence. n-Chimaerin mRNA was detectable in embryonic rat brain at day 15 and increased in amount postnatally from birth to 20 days, coincident with cellular differentiation and synaptogenesis. n-Chimaerin mRNA is restricted to neurons, with highest concentrations in hippocampal pyramidal cells, granule cells of the dentate gyrus and cortical neurons. In the cerebellum the mRNA was detected only in Purkinje neurons. The pattern and specificity of mRNA expression suggests an important role for n-chimaerin in neuronal signal-transduction mechanisms.