Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P62988 (Ubiquitin)
 4,326 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Ubiquitin/proteasome-mediated proteolysis plays an important role in the response to several environmental stresses. Here, we described the relationship of the proteolysis in the flooding stress in soybean (Glycine max L. cultivar Enrei). Immunoblot analyses were performed using antibodies against two subunits of 26S proteasome, Rpt5 and Rpn10, 20S proteasome and two subunits of COP9 signalosome (CSN), CSN4 and CSN5, to compare between flooded and untreated roots. We also examined their protein amounts in the condition of low oxygen. Moreover, crude extracts from flooded or untreated roots incubated with or without a proteasome inhibitor MG132 were analyzed by proteomics technique. We revealed that the amount of ubiquitinated proteins in soybean roots decreased after flooding treatment and increased to levels similar to controls after de-submergence. Both CSN4 and CSN5 accumulated following flooding treatment, although no significant difference was observed in proteasome. Low oxygen had no effect on the amount of ubiquitinated proteins or CSN4. By 2D-PAGE, the amount of 6 proteins changed significantly following MG132 treatment in flooding stressed plants. We conclude that the accumulation of CSN proteins might enhance the degradation of ubiquitinated proteins independent of hypoxia caused by flooding, thereby lowering their abundance during flooding stress.
 ...
PMID:Ubiquitin/proteasome-mediated proteolysis is involved in the response to flooding stress in soybean roots, independent of oxygen limitation. 2232 88

The COP9 signalosome (CSN) plays an important role in proteasome-mediated degradation by regulating CUL1 rubylation of the SCF ligase and is involved in many crucial biological processes. Here, we demonstrate a link between IDEF1 accumulation and the decline in COP9 derubylation activity in response to iron deficiency (-Fe) in rice (Oryza sativa). CSN6 expression is rapidly down-regulated during Fe depletion, contributing to reduced CSN activity, as judged by CSN5 and CUL1 expression, indicating CSN6 is involved in the early stage response of -Fe. In contrast to CSN6, the IDEF1 protein and expression of several iron uptake/utilisation-related genes are increased in response to -Fe. Thus, we constructed CSN6 transgenic sense and antisense lines and found that experimental depletion of CSN6 results in accumulation of the IDEF1 protein and up-regulation of several iron uptake/utilisation-related genes. Furthermore, IDEF1 can be decorated with K48-linked polyubiquitin and degraded via the 26S proteasome. Accumulated IDEF1 in antisense lines led to increased chlorophyll and Fe content in seedlings during -Fe. Collectively, the cellular CSN6 level is decreased during early stages of -Fe to ensure the rapid accumulation of IDEF1, which in turn up-regulates several iron uptake/utilisation-related genes to help overcome -Fe stress in rice.
 ...
PMID:CSN6, a subunit of the COP9 signalosome, is involved in early response to iron deficiency in Oryza sativa. 2713 67