To discover genes involved in nitric oxide (NO) metabolism, a genetic screen was employed to identify mutants defective in NO accumulation after treatment with the physiological inducer hydrogen peroxide. In wild-type Arabidopsis thaliana plants, NO levels increase eightfold in roots after H(2)O(2) treatment for 30 min. A mutant defective in H(2)O(2)-induced NO accumulation was identified, and the corresponding mutation was mapped to the prohibitin gene PHB3, converting the highly conserved Gly-37 to an Asp in the protein's SPFH domain. This point mutant and a T-DNA insertion mutant were examined for other NO-related phenotypes. Both mutants were defective in abscisic acid-induced NO accumulation and stomatal closure and in auxin-induced lateral root formation. Both mutants were less sensitive to salt stress, showing no increase in NO accumulation and less inhibition of primary root growth in response to NaCl treatment. In addition, light-induced NO accumulation was dramatically reduced in cotyledons. We found no evidence for impaired H(2)O(2) metabolism or signaling in the mutants as H(2)O(2) levels and H(2)O(2)-induced gene expression were unaffected by the mutations. These findings identify a component of the NO homeostasis system in plants and expand the function of prohibitin genes to include regulation of NO accumulation and NO-mediated responses.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2828708 | PMC |
http://dx.doi.org/10.1105/tpc.109.072066 | DOI Listing |
Ren Fail
December 2025
Department of Urology, The First Affiliated Hospital of Guangxi Medical University, Nanning, China.
Adv Gerontol
January 2025
Belgorod State National Research University, 85 build. 10 Pobedy str., Belgorod 308015, Russian Federation, e-mail:
Front Plant Sci
November 2024
Zhejiang Key Laboratory of Intelligent Food Logistic and Processing, College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo, China.
Nat Commun
November 2024
Department of Biology, University of Pennsylvania, Philadelphia, PA, 19104, USA.
Functional divergence of transcription factors (TFs) has driven cellular and organismal complexity throughout evolution, but its mechanistic drivers remain poorly understood. Here we test for new mechanisms using CORONA (CNA) and PHABULOSA (PHB), two functionally diverged paralogs in the CLASS III HOMEODOMAIN LEUCINE ZIPPER (HD-ZIPIII) family of TFs. We show that virtually all genes bound by PHB ( ~ 99%) are also bound by CNA, ruling out occupation of distinct sets of genes as a mechanism of functional divergence.
View Article and Find Full Text PDFMicrobiol Spectr
November 2024
School of Life Science, Soochow University, Suzhou, China.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!