The mechanism of mhz3 of rice ethylene insensitive mutants was analyzed.

Ethylene plays an important regulatory role in the growth and development of plants and in the response of the environment.
EIN2 is the central component of ethylene signal transduction, and its N-end is a Nramp-like domain of 12 trans-membrane regions, similar to the mammalian Nramp Ion Channel, and the C end is a hydrophilic domain located in the cytoplasm.
Although the biochemical function of EIN2 C end has been widely studied, that is, ethylene processing causes the C-end protein to be shearing from the endosomeand and cytoplasmic processing small body (P-body) to activate the downstream signal components, the importance and regulatory mechanism of its N-end transmembrane region in ethylene signal transduction is not clear.
recently, Zhang Jinsong of the Institute of Genetics and Developmental Biology of the Chinese Academy of Sciences and Chen Yi's research group, through the analysis of rice ethylene insensitive mutant mhz3 (Figure A), the identification of membrane protein MHZ3 and through the influence of EIN2 N-end transmembrane region to promote the role of ethylene signal transduction mechanism.
MHZ3 encodes an endogenous membrane protein whose expression is induced by ethylene on average in transcription and protein-water.
the molecular mechanism of MHZ3.
(A)mhz3 mutant ethylene reactive phenotype.
Air: Air Treatment.
ET: Ethylene treatment.
(B)MHZ3 stable OsEIN2 protein working model. the N and C ends of the
MHZ3 can be combined with the N-end trans membrane region of OsEIN2 to inhibit its ubiquity and degradation, thus stabilizing OsEIN2 and ethylene signal transduction.
genetic analysis, MHZ3 is especially in the ethylene signaling pathway in OsEIN2.
its lack of function led to a decrease in the stability of OsEIN2 protein and hindered the accumulation of ethylene-induced OsEIN2 protein, while excessive expression of MHZ3 significantly improved OsEIN2 protein abundance. Further studies
found that MHZ3 and OsEIN2 proteins interact directly, and both the N and C ends are combined on the Nramp-like domain of osEIN2 N-end inter-membrane region.
the interaction of the two can effectively inhibit OsEIN2 ubiquity, is necessary to stabilize OsEIN2 protein.
, the ethylene-induced MHZ3 protein can be inhibited by binding the OsEIN2 Nramp-like domain to inhibit its ubiquity and thus stabilize the OsEIN2 protein to maintain the ethylene reaction (Figure B).
this study reveals the new regulatory factor MHZ3 and the mechanism of action of ethylene signal, and strengthens the potential mechanism of EIN2 to mediate upstream ethylene signal through its N-end Nramp-like domain, and expands the new idea of EIN2 research. The results of the study were published online on February 20,
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Associate Researcher Ma Wei is the first author of the paper, and Zhou Yang, a doctoral student, and Chen Hui, a graduate, are the co-first authors.
research has been supported by the National Natural Science Foundation of China and the National Key Basic Research and Development Program (973 Program).
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