Modular Evolution and Population Variability of Oikopleura dioica Metallothioneins

Bibliographic Details
Title: Modular Evolution and Population Variability of Oikopleura dioica Metallothioneins
Authors: Sara Calatayud, Mario Garcia-Risco, Mercè Capdevila, Cristian Cañestro, Òscar Palacios, Ricard Albalat
Source: Frontiers in Cell and Developmental Biology, Vol 9 (2021)
Publisher Information: Frontiers Media S.A., 2021.
Publication Year: 2021
Collection: LCC:Biology (General)
Subject Terms: appendicularian tunicate chordates, modular protein evolution, metallothionein domains, tandem domain repeats, population variants, intra-species variability, Biology (General), QH301-705.5
More Details: Chordate Oikopleura dioica probably is the fastest evolving metazoan reported so far, and thereby, a suitable system in which to explore the limits of evolutionary processes. For this reason, and in order to gain new insights on the evolution of protein modularity, we have investigated the organization, function and evolution of multi-modular metallothionein (MT) proteins in O. dioica. MTs are a heterogeneous group of modular proteins defined by their cysteine (C)-rich domains, which confer the capacity of coordinating different transition metal ions. O. dioica has two MTs, a bi-modular OdiMT1 consisting of two domains (t-12C and 12C), and a multi-modular OdiMT2 with six t-12C/12C repeats. By means of mass spectrometry and spectroscopy of metal-protein complexes, we have shown that the 12C domain is able to autonomously bind four divalent metal ions, although the t-12C/12C pair –as it is found in OdiMT1– is the optimized unit for divalent metal binding. We have also shown a direct relationship between the number of the t-12C/12C repeats and the metal-binding capacity of the MTs, which means a stepwise mode of functional and structural evolution for OdiMT2. Finally, after analyzing four different O. dioica populations worldwide distributed, we have detected several OdiMT2 variants with changes in their number of t-12C/12C domain repeats. This finding reveals that the number of repeats fluctuates between current O. dioica populations, which provides a new perspective on the evolution of domain repeat proteins.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2296-634X
Relation: https://www.frontiersin.org/articles/10.3389/fcell.2021.702688/full; https://doaj.org/toc/2296-634X
DOI: 10.3389/fcell.2021.702688
Access URL: https://doaj.org/article/4bd6d9db1cdc4622ae8fc569435251d5
Accession Number: edsdoj.4bd6d9db1cdc4622ae8fc569435251d5
Database: Directory of Open Access Journals
More Details
ISSN:2296634X
DOI:10.3389/fcell.2021.702688
Published in:Frontiers in Cell and Developmental Biology
Language:English