TY - JOUR
T1 - lem7, a novel temperature-sensitive Arabidopsis mutation that reversibly inhibits vegetative development
AU - Meisel, Lee
AU - Xie, Shaoping
AU - Lam, Eric
N1 - Funding Information:
We thank Russ Ott and Pamela J. Green for the EMS mutagenized seeds, the Nottingham Arabidopsis Stock Centre for the wild-type Arabidopsis (ecotype Columbia) and the Arabidopsis Biological Resource Center at Ohio State University for the Ler (CS20) seeds. We also thank Karen Kim for her technical assistance, Ron Mittler for his assistance in screening for alleles of lem7, and Lee Simon for his assistance with the SEM. Furthermore, we thank June Medford, Ron Mittler, and Diane Shevell for their critical review of the manuscript. This work is supported by funding from the New Jersey Commission of Science and Technology.
PY - 1996/10/10
Y1 - 1996/10/10
N2 - An important question in developmental biology concerns the mechanisms by which a few cells coordinate division and differentiation to yield the complex structures and organs found in multicellular organisms. During vegetative growth in plants, cells in the apical meristem must coordinate division and differentiation to yield the fully mature leaf organ. Alterations in these processes may result in an abnormal leaf. In this paper we present the isolation and characterization of an EMS-generated, cold-temperature-sensitive mutation in Arabidopsis thaliana designated lem7 (leaf morphogenesis). lem7 is a semidominant mutation that maps to a novel locus on chromosome 2. When grown at 16°C, lem7 reversibly arrests leaf development at the shoot apex. In contrast, lem7 grown at 30°C appears phenotypically normal. Our data also suggest that the Lem7 locus may not be involved solely in leaf organogenesis, but may also play a role in noral development and the maintenance of patterns and structures after cellular differentiation. At an intermediate temperature of 23°C, leaves on the lem7 plant emerged phenotypically normal but began to show drastic changes at about 13 days postgermination. These changes include a reduced bilateral symmetry, a rough leaf lamina, a reduced number of trichomes, and an altered vascular network. Leaves that developed at the permissive temperature (30°C) and shifted to the nonpermissive temperature (16°C) form tumor-like outgrowths. Histological analysis of these tumor-like outgrowths and leaves grown at the intermediate temperature reveal abnormally large mesophyll cells, a disorganized mesophyll layer, and collapsed epidermal cells. We propose that the reversible inhibition of leaf development in lem7 under nonpermissive temperatures may serve as a useful tool for identifying genes involved in Arabidopsis leaf organogenesis.
AB - An important question in developmental biology concerns the mechanisms by which a few cells coordinate division and differentiation to yield the complex structures and organs found in multicellular organisms. During vegetative growth in plants, cells in the apical meristem must coordinate division and differentiation to yield the fully mature leaf organ. Alterations in these processes may result in an abnormal leaf. In this paper we present the isolation and characterization of an EMS-generated, cold-temperature-sensitive mutation in Arabidopsis thaliana designated lem7 (leaf morphogenesis). lem7 is a semidominant mutation that maps to a novel locus on chromosome 2. When grown at 16°C, lem7 reversibly arrests leaf development at the shoot apex. In contrast, lem7 grown at 30°C appears phenotypically normal. Our data also suggest that the Lem7 locus may not be involved solely in leaf organogenesis, but may also play a role in noral development and the maintenance of patterns and structures after cellular differentiation. At an intermediate temperature of 23°C, leaves on the lem7 plant emerged phenotypically normal but began to show drastic changes at about 13 days postgermination. These changes include a reduced bilateral symmetry, a rough leaf lamina, a reduced number of trichomes, and an altered vascular network. Leaves that developed at the permissive temperature (30°C) and shifted to the nonpermissive temperature (16°C) form tumor-like outgrowths. Histological analysis of these tumor-like outgrowths and leaves grown at the intermediate temperature reveal abnormally large mesophyll cells, a disorganized mesophyll layer, and collapsed epidermal cells. We propose that the reversible inhibition of leaf development in lem7 under nonpermissive temperatures may serve as a useful tool for identifying genes involved in Arabidopsis leaf organogenesis.
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U2 - 10.1006/dbio.1996.0245
DO - 10.1006/dbio.1996.0245
M3 - Article
C2 - 8873758
AN - SCOPUS:0030579164
SN - 0012-1606
VL - 179
SP - 116
EP - 134
JO - Developmental Biology
JF - Developmental Biology
IS - 1
ER -