Open AccessEvidence for the localization of the nuclear‐coded 22‐kDa heat‐shock protein in a subfraction of thylakoid membranes
Author(s) -
ADAMSKA Iwona,
KLOPPSTECH Klaus
Publication year - 1991
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1991.tb16025.x
Subject(s) - thylakoid , chloroplast , membrane , stroma , heat shock protein , biochemistry , chemistry , chloroplast membrane , integral membrane protein , biophysics , membrane protein , biology , microbiology and biotechnology , gene , immunohistochemistry , immunology
The precursor to the nuclear‐coded 22‐kDa heat‐shock protein of chloroplasts (HSP 22) has been transported into isolated intact chloroplasts from heat‐shocked plants. The localization of the mature protein in the chloroplast membrane was investigated. We have shown that the processed HSP 22 of pea was not bound to envelopes and found predominantly in thylakoid membranes. The binding of HSP 22 was stable in the presence of high salt concentrations. Solubilization of thylakoid membranes with Triton X‐100 and phase partitioning with Triton X‐114 indicate an intrinsic localization of HSP 22 or, alternatively, a non‐covalent association with integral membrane protein(s). After fractionation into grana and stroma lamellae, HSP 22 was found mostly in the grana‐membrane subfraction.