TY - JOUR
T1 - A mutation affecting the synthesis of 4-chloroindole-3-acetic acid
AU - Ross, John J.
AU - Tivendale, Nathan D.
AU - Davidson, Sandra E.
AU - Reid, James B.
AU - Davies, Noel W.
AU - Quittenden, Laura J.
AU - Smith, Jason A.
PY - 2012
Y1 - 2012
N2 - Traditionally, schemes depicting auxin biosynthesis in plants have been notoriously complex. They have involved up to four possible pathways by which the amino acid tryptophan might be converted to the main active auxin, indole-3-acetic acid (IAA), while another pathway was suggested to bypass tryptophan altogether. It was also postulated that different plants use different pathways, further adding to the complexity. In 2011, however, it was suggested that one of the four tryptophan-dependent pathways, via indole-3-pyruvic acid (IPyA), is the main pathway in Arabidopsis thaliana,1 although concurrent operation of one or more other pathways has not been excluded. We recently showed that, for seeds of Pisum sativum (pea), it is possible to go one step further.2 Our new evidence indicates that the IPyA pathway is the only tryptophan-dependent IAA synthesis pathway operating in pea seeds. We also demonstrated that the main auxin in developing pea seeds, 4-chloroindole-3-acetic acid (4-Cl-IAA), which accumulates to levels far exceeding those of IAA, is synthesized via a chlorinated version of the IPyA pathway.
AB - Traditionally, schemes depicting auxin biosynthesis in plants have been notoriously complex. They have involved up to four possible pathways by which the amino acid tryptophan might be converted to the main active auxin, indole-3-acetic acid (IAA), while another pathway was suggested to bypass tryptophan altogether. It was also postulated that different plants use different pathways, further adding to the complexity. In 2011, however, it was suggested that one of the four tryptophan-dependent pathways, via indole-3-pyruvic acid (IPyA), is the main pathway in Arabidopsis thaliana,1 although concurrent operation of one or more other pathways has not been excluded. We recently showed that, for seeds of Pisum sativum (pea), it is possible to go one step further.2 Our new evidence indicates that the IPyA pathway is the only tryptophan-dependent IAA synthesis pathway operating in pea seeds. We also demonstrated that the main auxin in developing pea seeds, 4-chloroindole-3-acetic acid (4-Cl-IAA), which accumulates to levels far exceeding those of IAA, is synthesized via a chlorinated version of the IPyA pathway.
KW - Auxin synthesis
KW - Halogenation
KW - Indole-3-pyruvic acid
KW - Tryptophan aminotransferase
UR - http://www.scopus.com/inward/record.url?scp=84871196859&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84871196859&partnerID=8YFLogxK
U2 - 10.4161/psb.22319
DO - 10.4161/psb.22319
M3 - Article
C2 - 23073010
AN - SCOPUS:84871196859
SN - 1559-2316
VL - 7
SP - 1533
EP - 1536
JO - Plant Signaling and Behavior
JF - Plant Signaling and Behavior
IS - 12
ER -