期刊
MOLECULAR BIOLOGY AND EVOLUTION
卷 33, 期 12, 页码 3226-3248出版社
OXFORD UNIV PRESS
DOI: 10.1093/molbev/msw209
关键词
silicon; eukaryotes; SIT; Lsi2; convergent evolution; transporter
资金
- EDEN Evo-Dev-Eco Network Research Exchange Fund
- Musgrave Pratt Fund (Department of Zoology, University of Cambridge)
- Parke-Davis Fund (University of Cambridge)
- European Research Council [247333]
- Wellcome Trust
- European Research Council under the European Union's Seventh Framework Programme [282101]
- National Environmental Research Council [NE/J021954/1]
- Howard Hughes Medical Institute
- Japan Science and Technology Agency-Centre National de la Recherche Scientifique program
- National Defense Science and Engineering Graduate fellowship from the United States Department of Defense
- National Science Foundation Central Europe Summer Research Institute Fellowship
- Chang-Lin Tien Fellowship in Environmental Sciences and Biodiversity
- Conseil Regional de Bretagne
- French Government Investissements d'Avenir program OCEANOMICS [ANR-11-BTBR-0008]
- European Research Council (ERC) [282101] Funding Source: European Research Council (ERC)
- Natural Environment Research Council [NE/N011708/1] Funding Source: researchfish
- NERC [NE/N011708/1] Funding Source: UKRI
Biosilicification (the formation of biological structures from silica) occurs in diverse eukaryotic lineages, plays a major role in global biogeochemical cycles, and has significant biotechnological applications. Silicon (Si) uptake is crucial for biosilicification, yet the evolutionary history of the transporters involved remains poorly known. Recent evidence suggests that the SIT family of Si transporters, initially identified in diatoms, may be widely distributed, with an extended family of related transporters (SIT-Ls) present in some nonsilicified organisms. Here, we identify SITs and SIT-Ls in a range of eukaryotes, including major silicified lineages (radiolarians and chrysophytes) and also bacterial SIT-Ls. Our evidence suggests that the symmetrical 10-transmembrane-domain SIT structure has independently evolved multiple times via duplication and fusion of 5-transmembrane-domain SIT-Ls. We also identify a second gene family, similar to the active Si transporter Lsi2, that is broadly distributed amongst siliceous and nonsiliceous eukaryotes. Our analyses resolve a distinct group of Lsi2-like genes, including plant and diatom Si-responsive genes, and sequences unique to siliceous sponges and choanoflagellates. The SIT/SIT-L and Lsi2 transporter families likely contribute to biosilicification in diverse lineages, indicating an ancient role for Si transport in eukaryotes. We propose that these Si transporters may have arisen initially to prevent Si toxicity in the high Si Precambrian oceans, with subsequent biologically induced reductions in Si concentrations of Phanerozoic seas leading to widespread losses of SIT, SIT-L, and Lsi2-like genes in diverse lineages. Thus, the origin and diversification of two independent Si transporter families both drove and were driven by ancient ocean Si levels.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据