Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2009-2-2
pubmed:abstractText
In contrast to auxin, relatively little is known about the molecular mechanism of cytokinin (CTK) inhibition of lateral root initiation. Previous studies demonstrated that BREVIS RADIX (BRX), a protein of unknown biochemical function, maintains a rate-limiting brassinosteroid biosynthesis enzyme expression to keep brassinosteroid biosynthesis above a critical threshold. Here, we show that the brx-2 mutant is insensitive to exogenous CTK-induced inhibition of lateral root initiation and that this can be restored by embryonic brassinosteroid treatment. However post-embryonic brassinosteroid treatment can not rescue brx-2 mutant phenotype in the presence of CTK. Meanwhile the brassinosteroid receptor defective mutant bri1-6 shows normal CTK-mediated inhibition on LR growth. These results suggest the CTK-mediated inhibition of LR initiation is not directly dependent on brassinosteroid level. Furthermore, compared with wild type, brx-2 exhibits altered auxin response in presumptive founder cells, lateral root primodia and primary root tip in the presence of exogenous CTK. We concluded that CTK inhibition on lateral root initiation depend on specific auxin response loss in presumptive founder cell. The aberrant primary root growth caused by the embryonic brassinosteroid shortage can indirectly result in the lateral root phenotype of brx-2 in presence of CTK.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0032-0935
pubmed:author
pubmed:issnType
Print
pubmed:volume
229
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
593-603
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
BREVIS RADIX is involved in cytokinin-mediated inhibition of lateral root initiation in Arabidopsis.
pubmed:affiliation
Zhejiang University, Hangzhou, People's Republic of China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't