Basal Gnathostomes Provide Unique Insights into the Evolution of Vitamin B12 Binders

• Type: Article in International Scientific Journal
• Date: 2015

Authors

Lopes Marques, M (Author) Other; Ruivo, R (Author) Other; Delgado, I (Author) Other; Wilson, JM (Author) Other; Aluru, N (Author) Other; Filipe F C Castro (Author) FCUP

Journal

Title: Genome Biology and Evolution

Vol. 7

Pages: 457-464

ISSN: 1759-6653

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 6 Citations

Scopus - 6 Citations

Other information

Authenticus ID: P-00A-A0E

DOI: 10.1093/gbe/evu289

Abstract (EN): The uptake and transport of vitamin B12 (cobalamin; CIA in mammals involves a refined system with three evolutionarily related transporters: transcobalamin 1 (Toni), transcobalamin 2 (Ton2), and the gastric intrinsic factor (Gif). Teleosts have a single documented binder with intermediate features to the human counterparts. Consequently, it has been proposed that the expansion of Cbl binders occurred after the separation of Actinopterygians. Here, we demonstrate that the diversification of this gene family took place earlier in gnathostome ancestry. Our data indicates the presence of single copy orthologs of the Sarcopterygiiiretrapoda duplicates Toil and Gif, and Tcn2, in Chondrichthyes. In addition, a highly divergent Cbl binder was found in the Elasmobranchii. We unveil a complex scenario forged by genome, tandem duplications and lineage-specific gene loss. Our findings suggest that from an ancestral transporter, exhibiting large spectrum and high affinity binding, highly specific Cbl transporters emerged through gene duplication and mutations at the binding pocket.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8