Dataset Information

Evolutionary convergence and divergence in archaeal chromosomal proteins and Chromo-like domains from bacteria and eukaryotes.

ABSTRACT: SH3-fold-?-barrel domains of the chromo-like superfamily recognize epigenetic marks in eukaryotic proteins. Their provenance has been placed either in archaea, based on apparent structural similarity to chromatin-compacting Sul7d and Cren7 proteins, or in bacteria based on the presence of sequence homologs. Using sequence and structural evidence we establish that the archaeal Cren7/Sul7 proteins emerged from a zinc ribbon (ZnR) ancestor. Further, we show that the ancestral eukaryotic chromo-like domains evolved from bacterial versions, likely acquired from early endosymbioses, which already possessed an aromatic cage for recognition of modified amino-groups. These bacterial versions are part of a radiation of secreted SH3-fold domains, which spawned both chromo-like domains and classical SH3 domains in the context of peptide-recognition in the peptidoglycan or the extracellular matrix. This establishes that Cren7/Sul7 converged to a "SH3"-like state from a ZnR precursor via the loss of metal-chelation and acquisition of stronger hydrophobic interactions; it is unlikely to have participated in the evolution of the chromo-like domains. We show that archaea possess several Cren7/Sul7-related proteins with intact Zn-chelating ligands, which we predict to play previously unstudied roles in chromosome segregation during cell-division comparable to the PRC barrel and CdvA domain proteins.

SUBMITTER: Kaur G

PROVIDER: S-EPMC5906684 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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Evolutionary convergence and divergence in archaeal chromosomal proteins and Chromo-like domains from bacteria and eukaryotes.

Kaur Gurmeet G Iyer Lakshminarayan M LM Subramanian Srikrishna S Aravind L L

Scientific reports 20180418 1

SH3-fold-β-barrel domains of the chromo-like superfamily recognize epigenetic marks in eukaryotic proteins. Their provenance has been placed either in archaea, based on apparent structural similarity to chromatin-compacting Sul7d and Cren7 proteins, or in bacteria based on the presence of sequence homologs. Using sequence and structural evidence we establish that the archaeal Cren7/Sul7 proteins emerged from a zinc ribbon (ZnR) ancestor. Further, we show that the ancestral eukaryotic chromo-like ...[more]

PMID: 29670199

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Dataset Information

Evolutionary convergence and divergence in archaeal chromosomal proteins and Chromo-like domains from bacteria and eukaryotes.

Publications

Evolutionary convergence and divergence in archaeal chromosomal proteins and Chromo-like domains from bacteria and eukaryotes.

Similar Datasets

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