Biochemical characterization of gamma-aminobutyric acid (GABA): pyruvate transaminase during rice leaf senescence
نویسندگان
چکیده
Senescence-associated genes (SAGs) are up-regulated during plant senescence and may have been implicated in encoding enzymes involved in metabolism of senescence tissues. The gene Osl2 (GABA:pyruvate-transaminase) which is upregulated during leaf senescence in rice (Oryza sativa) was functionally characterized. The recombinant Osl2 fusion protein over-expressed in Escherichia coli displays pyruvate-dependent gammaaminobutyric acid (GABA) transaminase (EC 2.6.1.19) activity. Investigations of the corresponding pyruvatedependent GABA transaminase activities in rice leaves demonstrate the up-regulation of enzyme activity during leaf senescence, with the highest activity at the S3 stage of rice leaf senescence. Here we have discussed the role of GABA:pyruvate-transaminase in the metabolism of amino acids and nitrogen recycle during rice leaf senescence.
منابع مشابه
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