Evolution of retinoic acid receptors in chordates: insights from three lamprey species, Lampetra fluviatilis, Petromyzon marinus, and Lethenteron japonicumReportar como inadecuado

Evolution of retinoic acid receptors in chordates: insights from three lamprey species, Lampetra fluviatilis, Petromyzon marinus, and Lethenteron japonicum - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

* Corresponding author 1 Molecular Zoology Team 2 ENS Lyon - École normale supérieure - Lyon 3 Department of ecology and evolutionary biology 4 Department of zoology 5 Laboratory for evolutionary morphology 6 Department of pediatrics 7 Department of biology 8 Division of pediatric gastroenterology 9 SBR - Station biologique de Roscoff Roscoff 10 GRAS - Genome Resource and Analysis Unit 11 Phyloinformatics Unit 12 LBDV - Laboratoire de Biologie du Développement de Villefranche sur mer

Abstract : Background : Retinoic acid RA signaling controls many developmental processes in chordates, from early axis specification to late organogenesis. The functions of RA are chiefly mediated by a subfamily of nuclear hormone receptors, the retinoic acid receptors RARs, that act as ligand-activated transcription factors. While RARs have been extensively studied in jawed vertebrates that is, gnathostomes and invertebrate chordates, very little is known about the repertoire and developmental roles of RARs in cyclostomes, which are extant jawless vertebrates. Here, we present the first extensive study of cyclostome RARs focusing on three different lamprey species: the European freshwater lamprey, Lampetra fluviatilis, the sea lamprey, Petromyzon marinus, and the Japanese lamprey, Lethenteron japonicum.Results : We identified four rar paralogs rar1, rar2, rar3, and rar4 in each of the three lamprey species, and phylogenetic analyses indicate a complex evolutionary history of lamprey rar genes including the origin of rar1 and rar4 by lineage-specific duplication after the lamprey-hagfish split. We further assessed their expression patterns during embryonic development by in situ hybridization. The results show that lamprey rar genes are generally characterized by dynamic and highly specific expression domains in different embryonic tissues. In particular, lamprey rar genes exhibit combinatorial expression domains in the anterior central nervous system CNS and the pharyngeal region.Conclusions : Our results indicate that the genome of lampreys encodes at least four rar genes and suggest that the lamprey rar complement arose from vertebrate-specific whole genome duplications followed by a lamprey-specific duplication event. Moreover, we describe a combinatorial code of lamprey rar expression in both anterior CNS and pharynx resulting from dynamic and highly specific expression patterns during embryonic development. This ‘RAR code’ might function in regionalization and patterning of these two tissues by differentially modulating the expression of downstream effector genes during development.

Keywords : Vertebrate Gnathostome Gene duplication Cyclostome Agnathan RAR code Retinoid signaling Developmental patterning

Autor: Florent Campo-Paysaa - David Jandzik - Yoko Takio-Ogawa - Maria V Cattell - Haley C Neef - James A Langeland - Shigeru Kuratani -

Fuente: https://hal.archives-ouvertes.fr/


Documentos relacionados