Oikopleura dioica clone BACOIKO003 5xk14, two esterase like sequences e4y7i7 allelic scaffoldA_35
Comment
This long sequence is formed of two esterase like sequences and a module Zona_pellucida. Here it has been split in two . Pfam A Zona_pellucida 21 274 COesterase 337 868 and 989 1521
(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Metazoa: NE > Eumetazoa: NE > Bilateria: NE > Deuterostomia: NE > Chordata: NE > Tunicata: NE > Appendicularia: NE > Oikopleuridae: NE > Oikopleura: NE > Oikopleura dioica: NE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA PNHGLPEMTYDSELVDENLLHAPENLKREGFCIDENGQATLTLSDGTVFI GQDRDGVVDFRGVPYAIPPLEQMRWTQPLVKLNFEGQTYDFTDFGDACAQ HHHADGTSEDCLNINISVPRDALEEGRLVPIIYVVHGGGFNHGNNRWRSS DLIKKEQVAIFNIGYRFGIFGFYTLPEVEQGQNFQTNWGLQDPVAAMAFT QTYGPIFGGDPDNASFSARSSGAEIVWRLLTVPCAWPYFKRVNMMNMGLN TEYPLEHAPKLRDVVYGELNCSDTPCMRAQEHDDLAHAGDAAAYGARHPS KITLEPGFGMVVDGRFGRQQLMFDVRDGNVRPHTPIAWSYSEHDNWAFNH LAFANSMYKFMTDKLGDIAAAKAATGHKVPYPYANQLIERFYANYDDISA VEEVFFCEDNGEDCNDIFSKWVNSMNWVCNTRWGLKGALSNPEEFPELGP LYVTQFSAKNCDPDPVTGDYRKTCHTGEGPFVYGDYNLKVIDDNLGRLYY DMSAKTSVWLVDRMRSAWGSYFRTGEFPAGTIEKWSEIEDEEHETYNIIS PENGYNWATAKTYVDECRALDQFHYDDCAENDYIVATSEG
Genomes of animals as different as sponges and humans show conservation of global architecture. Here we show that multiple genomic features including transposon diversity, developmental gene repertoire, physical gene order, and intron-exon organization are shattered in the tunicate Oikopleura, belonging to the sister group of vertebrates and retaining chordate morphology. Ancestral architecture of animal genomes can be deeply modified and may therefore be largely nonadaptive. This rapidly evolving animal lineage thus offers unique perspectives on the level of genome plasticity. It also illuminates issues as fundamental as the mechanisms of intron gain.
Homeodomain transcription factors are involved in many developmental processes and have been intensely studied in a few model organisms, such as mouse, Drosophila and Caenorhabditis elegans. Homeobox genes fall into 10 classes (ANTP, PRD, POU, LIM, TALE, SIX, Cut, ZFH, HNF1, Prox) and 89 different families/groups, all of which are present in vertebrates. Additional groups may be uncovered by further genome annotation, particularly of complex vertebrate genomes. Eight of these groups have been found only in vertebrates, but not in the genome of the tunicate Ciona intestinalis. The other 81 groups of homeobox gene that have been detected in vertebrates so far probably appeared during the early evolution of bilaterians or earlier, as they are also present outside the chordates. How the homeobox genes evolved during and after the main radiation of the bilaterians remains poorly understood, as only a few animal genomes have been sequenced completely. However, drastic changes have occurred at least in the lineage of C. elegans , such as loss of several Hox genes and Hox cluster fragmentation . Here we report considerable alterations of the homeobox gene complement in the tunicate lineage.
Tunicate embryos and larvae have small cell numbers and simple anatomical features in comparison with other chordates, including vertebrates. Although they branch near the base of chordate phylogenetic trees, their degree of divergence from the common chordate ancestor remains difficult to evaluate. Here we show that the tunicate Oikopleura dioica has a complement of nine Hox genes in which all central genes are lacking but a full vertebrate-like set of posterior genes is present. In contrast to all bilaterians studied so far, Hox genes are not clustered in the Oikopleura genome. Their expression occurs mostly in the tail, with some tissue preference, and a strong partition of expression domains in the nerve cord, in the notochord and in the muscle. In each tissue of the tail, the anteroposterior order of Hox gene expression evokes spatial collinearity, with several alterations. We propose a relationship between the Hox cluster breakdown, the separation of Hox expression domains, and a transition to a determinative mode of development.
