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Structural basis of GDP release and gating in G protein coupled Fe2+ transport.

ABSTRACT: G proteins are key molecular switches in the regulation of membrane protein function and signal transduction. The prokaryotic membrane protein FeoB is involved in G protein coupled Fe(2+) transport, and is unique in that the G protein is directly tethered to the membrane domain. Here, we report the structure of the soluble domain of FeoB, including the G protein domain, and its assembly into an unexpected trimer. Comparisons between nucleotide free and liganded structures reveal the closed and open state of a central cytoplasmic pore, respectively. In addition, these data provide the first observation of a conformational switch in the nucleotide-binding G5 motif, defining the structural basis for GDP release. From these results, structural parallels are drawn to eukaryotic G protein coupled membrane processes.

SUBMITTER: Guilfoyle A

PROVIDER: S-EPMC2738704 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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Structural basis of GDP release and gating in G protein coupled Fe2+ transport.

Guilfoyle Amy A Maher Megan J MJ Rapp Mikaela M Clarke Ronald R Harrop Stephen S Jormakka Mika M

The EMBO journal 20090723 17

G proteins are key molecular switches in the regulation of membrane protein function and signal transduction. The prokaryotic membrane protein FeoB is involved in G protein coupled Fe(2+) transport, and is unique in that the G protein is directly tethered to the membrane domain. Here, we report the structure of the soluble domain of FeoB, including the G protein domain, and its assembly into an unexpected trimer. Comparisons between nucleotide free and liganded structures reveal the closed and o ...[more]

PMID: 19629046

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