Mutation in the Arabidopisis thaliana DEK1 calpain gene perturbs endosperm and embryo development while over-expression affects organ development globally.
A T-DNA insertion in the Arabidopsis thaliana DEK1 gene, encoding a calpain-like cysteine proteinase with a predicted membrane anchor, causes unorganized embryo development displaying irregular mitotic divisions in the embryo proper and suspensor. Embryo development is arrested at the globular stage, and the embryo proper lacks a defined protoderm. In the endosperm, the aleurone-like peripheral cell layer is partly or completely lacking. The Arabidopsis DEK1 wild-type transcript is expressed evenly throughout the endosperm and the embryo in developing seed as determined using in situ hybridization. The conclusion that the observed phenotype is caused by a T-DNA insertion in the Arabidopsis DEK1 gene is confirmed by complementation with the Arabidopisis DEK1 genomic sequence, as well as analysis of a second T-DNA insertion allele. Over-expression of the Arabidopsis DEK1 gene coding sequence under the control of the 35S promoter causes a number of developmental phenotypes, including a global lack of trichomes, leaves exhibiting improper dorsiventral symmetry and aberrant cell organization in flowers. We interpret the data to suggest a role for DEK1 in providing cells with positional clues for an appropriate developmental context within plant tissues.
Lid
Stein Erik
SE
Department of Plant and Environmental Sciences, Agricultural University of Norway, P.O. Box 5003, 1432 As, Norway.
Olsen
Lene
L
Nestestog
Ragnhild
R
Aukerman
Milo
M
Brown
Roy C
RC
Lemmon
Betty
B
Mucha
Mark
M
Opsahl-Sorteberg
Hilde-Gunn
HG
Olsen
Odd-Arne
OA
D000483:Alleles; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics*; D002154:Calpain / Q000235:genetics*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D008855:Microscopy, Electron, Scanning; D009154:Mutation; D010641:Phenotype; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure; D030821:Plants, Genetically Modified; D012639:Seeds / Q000235:genetics / Q000254:growth & development* / Q000648:ultrastructure
D029681:Arabidopsis Proteins; D002154:Calpain