Cheng R, Bradford S, Barnes D, Williams D, Hendricks J, Bailey G
Department of Food Science and Technology, Oregon State University, Corvallis 97331-6602, USA.
Mol Mar Biol Biotechnol. 1997 Mar;6(1):40-7.
An enriched zebrafish (Danio rerio) complementary DNA library was constructed for screening of ras-related genes, and a positive clone was isolated from one plate of 3 x 10(4) plaques. This clone, Zras-B1, carried an insert of 2592 base pairs (bp) with an open reading frame encoding a ras p21 protein of 188 amino acids. The deduced amino-terminal 86 amino acid residues and the carboxy-terminal CAAX binding motif are identical to mammalian ras. The full-length Zras-B1-encoded protein is most closely related to human N-ras (91% identity), with lesser homology to Ha-ras (84%) and Ki-ras (85%). Preliminary screening data also indicate other ras genes in zebrafish, at least one of which is also transcribed in adults. A Zras-B1-related 3.1-kb transcript was found to be abundant in embryos from zygote through gastrulation, and may be maternally derived.
构建了一个富集的斑马鱼（Danio rerio）互补DNA文库用于筛选与ras相关的基因，并从一盘3×10⁴个噬菌斑中分离出一个阳性克隆。这个克隆Zras-B1携带一个2592个碱基对（bp）的插入片段，其开放阅读框编码一个由188个氨基酸组成的ras p21蛋白。推导的氨基末端86个氨基酸残基和羧基末端CAAX结合基序与哺乳动物的ras相同。全长Zras-B1编码的蛋白与人类N-ras关系最为密切（同一性为91%），与Ha-ras（84%）和Ki-ras（85%）的同源性较低。初步筛选数据还表明斑马鱼中存在其他ras基因，其中至少有一个在成体中也有转录。发现一个与Zras-B1相关的3.1-kb转录本在从受精卵到原肠胚形成阶段的胚胎中大量存在，并且可能是母源的。
