Vlachakis N, Ellstrom D R, Sagerström C G
Department of Pharmacology, University of Massachusetts Medical School, Worcester, MA 01655, USA.
Dev Dyn. 2000 Jan;217(1):109-19. doi: 10.1002/(SICI)1097-0177(200001)217:1<109::AID-DVDY10>3.0.CO;2-8.
pbx genes encode homeodomain-containing transcriptional regulators that interact with other proteins to control embryogenesis and tumorigenesis. We present the characterization of a zebrafish pbx CDNA that appears to encode a novel family member, pbx4. pbx4 RNA is maternally deposited and is detected throughout the zebrafish embryo during blastula stages. It becomes excluded from ventroanterior structures at late gastrula stages and is detected within the forming central nervous system during segmentation stages. pbx4 expression overlaps with that of two other homeobox genes, hoxb1b and meis3, in the region of the presumptive caudal hindbrain during gastrula stages. In vitro binding experiments revealed that protein complexes containing Pbx4/Meis3 and Pbx4/Hoxb1b, but not Meis3/Hoxb1b could be generated. A novel trimeric complex containing Pbx4, Meis3, and Hoxb1b was also formed. We speculate that complexes with different combinations of Pbx4, Meis3, and Hoxb1b specify different developmental fates during vertebrate embryogenesis. Dev Dyn 2000;217:109-119.
PBX基因编码含同源结构域的转录调节因子，这些因子与其他蛋白质相互作用以控制胚胎发育和肿瘤发生。我们展示了一种斑马鱼PBX cDNA的特征，该cDNA似乎编码一个新的家族成员PBX4。PBX4 RNA是母源沉积的，在囊胚期的整个斑马鱼胚胎中都能检测到。在原肠胚晚期，它从腹前部结构中排除，在体节期在形成的中枢神经系统中被检测到。在原肠胚期，PBX4的表达与另外两个同源框基因hoxb1b和meis3在假定尾后脑区域的表达重叠。体外结合实验表明，可以产生含有Pbx4/Meis3和Pbx4/Hoxb1b的蛋白复合物，但不能产生Meis3/Hoxb1b复合物。还形成了一种含有Pbx4、Meis3和Hoxb1b的新型三聚体复合物。我们推测，含有不同组合的Pbx4、Meis3和Hoxb1b的复合物在脊椎动物胚胎发育过程中决定了不同的发育命运。《发育动力学》2000年；217:109 - 119。
