Hox gene expression in larval development of the polychaetes Nereis virens and Platynereis dumerilii (Annelida, Lophotrochozoa)

摘要: The bilaterian animals are divided into three great branches: the Deuterostomia, Ecdysozoa, and Lophotrochozoa. evolution of developmental mechanisms is less studied in Lophotrochozoa than other two clades. We have expression Hox genes during larval development lophotrochozoans, polychaete annelids Nereis virens Platynereis dumerilii. As reported previously, cluster N. consists at least 11 (de Rosa R, Grenier JK, Andreeva T, Cook CE, Adoutte A, Akam M, Carroll SB, Balavoine G, Nature, 399:772–776, 1999; TF, C, Korchagina NM, Dondua AK, Ontogenez 32:225–233, 2001); we also cloned nine P. mainly expressed descendants 2d blastomere, which form integument segments, ventral neural ganglia, pre-pygidial growth zone, pygidial lobe. Patterns similar for orthologous both nereids. In Nereis, Hox2, Hox3 activated before blastopore closure, while Hox1 Hox4 just after this. Hox5 Post2 first active metatrochophore stage, Hox7, Lox4, Lox2 late nectochaete stage only. During stages, staggered domains developing segments pattern suggests their involvement vectorial regionalization body along antero-posterior axis. gene nereids conforms to canonical patterns postulated evolutionary branches Bilateria, Ecdysozoa thus supporting conservatism function development.