HoxA Genes and the Fin-to-Limb Transition in Vertebrates

• Type: Another Publication in an International Scientific Journal
• Date: 2016

Authors

Leite Castro, J (Author) Other; Beviano, V (Author) Other; Rodrigues, P (Author) ICBAS; Freitas, R (Author) Other

Journal

Title: Journal of Developmental Biology

Vol. 4

Final page: 10

Publisher: MDPI

Indexing

ISI Web of Knowledge - 6 Citations

Scopus - 10 Citations

Other information

Authenticus ID: P-00K-DE4

DOI: 10.3390/jdb4010010

Abstract (EN): HoxA genes encode for important DNA-binding transcription factors that act during limb development, regulating primarily gene expression and, consequently, morphogenesis and skeletal differentiation. Within these genes, HoxA11 and HoxA13 were proposed to have played an essential role in the enigmatic evolutionary transition from fish fins to tetrapod limbs. Indeed, comparative gene expression analyses led to the suggestion that changes in their regulation might have been essential for the diversification of vertebrates' appendages. In this review, we highlight three potential modifications in the regulation and function of these genes that may have boosted appendage evolution: (1) the expansion of polyalanine repeats in the HoxA11 and HoxA13 proteins; (2) the origin of +a novel long-non-coding RNA with a possible inhibitory function on HoxA11; and (3) the acquisition of cis-regulatory elements modulating 5' HoxA transcription. We discuss the relevance of these mechanisms for appendage diversification reviewing the current state of the art and performing additional comparative analyses to characterize, in a phylogenetic framework, HoxA11 and HoxA13 expression, alanine composition within the encoded proteins, long-non-coding RNAs and cis-regulatory elements.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 17