TY - JOUR
T1 - Hormonal studies of fass, an arabidopsis mutant that is altered in organ elongation
AU - Fisher, Roxanne H.
AU - Barton, M. Kathryn
AU - Cohen, Jerry D.
AU - Cooke, Todd J.
PY - 1996/4
Y1 - 1996/4
N2 - We have isolated an allele of fass, an Arabidopsis thaliana mutation that separates plant development and organ differentiation from plant elongation, and studied its hormonal regulation. Microsurgically isolated fass roots elongate 2.5 times as much as the roots on intact mutant plants. Wild-type heart embryos, when cultured with a strong auxin, naphthaleneacetic acid, phenocopy fass embryos. fass seedlings contain variable levels of free auxin, which average 2.5 times higher than wild-type seedling levels, and fass seedlings evolve 3 times as much ethylene as wild-type seedlings on a per-plant basis over a 24-h period. The length-to-width ratios of fass seedlings can be changed by several compounds that affect their endogenous ethylene levels, but fass is epistatic to etr1, an ethylene-insensitive mutant. fass's high levels of free auxin may be inducing its high levels of ethylene, which may, in turn, result in the fass phenotype. We postulate that FASS may be acting as a negative regulator to maintain wild-type auxin levels and that the mutation may be in an auxin-conjugating enzyme.
AB - We have isolated an allele of fass, an Arabidopsis thaliana mutation that separates plant development and organ differentiation from plant elongation, and studied its hormonal regulation. Microsurgically isolated fass roots elongate 2.5 times as much as the roots on intact mutant plants. Wild-type heart embryos, when cultured with a strong auxin, naphthaleneacetic acid, phenocopy fass embryos. fass seedlings contain variable levels of free auxin, which average 2.5 times higher than wild-type seedling levels, and fass seedlings evolve 3 times as much ethylene as wild-type seedlings on a per-plant basis over a 24-h period. The length-to-width ratios of fass seedlings can be changed by several compounds that affect their endogenous ethylene levels, but fass is epistatic to etr1, an ethylene-insensitive mutant. fass's high levels of free auxin may be inducing its high levels of ethylene, which may, in turn, result in the fass phenotype. We postulate that FASS may be acting as a negative regulator to maintain wild-type auxin levels and that the mutation may be in an auxin-conjugating enzyme.
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U2 - 10.1104/pp.110.4.1109
DO - 10.1104/pp.110.4.1109
M3 - Article
AN - SCOPUS:0000072778
SN - 0032-0889
VL - 110
SP - 1109
EP - 1121
JO - Plant physiology
JF - Plant physiology
IS - 4
ER -