Igarashi T, Kuroda H, Takahashi S, Asashima M
Department of Life Sciences (Biology), Graduate School of Arts and Sciences, University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo, 153-8902, Japan.
Dev Growth Differ. 2001 Dec;43(6):693-8. doi: 10.1046/j.1440-169x.2001.00613.x.
The p8 gene encodes a transcription factor with a basic helix-loop-helix motif and has been cloned in rat, mouse and human. It is upregulated in acute pancreatitis. In the present study, the Xenopus laevis homolog of p8 (Xp8) was isolated by PCR. The full-length Xp8 cDNA consists of 677 bp and encodes 82 amino acids. The basic helix-loop-helix region is well conserved between X. laevis and mammals. Overexpression of an Xp8-EGFP fusion protein indicated that Xp8 was localized to nucleus, as in mammals. Analysis by RT-PCR showed that expression of Xp8 was increased after gastrulation and maintained into later developmental stages. Expression was detected in the prospective neural region at the neurula stage by whole-mount in situ hybridization. At the larval stage, Xp8 was expressed in central nervous regions, such as ventrolateral brain, trigeminal nerve, vestibulocochlear nerve and dorsal neural tube. Expression was also detected in the basal cement gland, olfactory placode, ear vesicle, notochord and anus. This specific pattern of expression suggests that Xp8 may play a role in the development of the central nervous system in X. laevis.
p8基因编码一种带有碱性螺旋-环-螺旋基序的转录因子，已在大鼠、小鼠和人类中克隆出来。它在急性胰腺炎中上调。在本研究中，通过聚合酶链反应（PCR）分离出非洲爪蟾p8（Xp8）的同源物。Xp8全长cDNA由677个碱基对组成，编码82个氨基酸。非洲爪蟾和哺乳动物之间的碱性螺旋-环-螺旋区域高度保守。Xp8-增强绿色荧光蛋白（EGFP）融合蛋白的过表达表明，与哺乳动物一样，Xp8定位于细胞核。逆转录-聚合酶链反应（RT-PCR）分析显示，原肠胚形成后Xp8的表达增加，并维持到后期发育阶段。通过整体原位杂交在神经胚阶段的预期神经区域检测到表达。在幼虫阶段，Xp8在中枢神经区域表达，如腹外侧脑、三叉神经、前庭蜗神经和背神经管。在基底黏液腺、嗅基板、耳泡、脊索和肛门中也检测到表达。这种特定的表达模式表明，Xp8可能在非洲爪蟾中枢神经系统的发育中发挥作用。
