CDKG1 protein kinase is essential for synapsis and male meiosis at high ambient temperature in Arabidopsis thaliana.
The Arabidopsis cyclin-dependent kinase G (CDKG) gene defines a clade of cyclin-dependent protein kinases related to CDK10 and CDK11, as well as to the enigmatic Ph1-related kinases that are implicated in controlling homeologous chromosome pairing in wheat. Here we demonstrate that the CDKG1/CYCLINL complex is essential for synapsis and recombination during male meiosis. A transfer-DNA insertional mutation in the cdkg1 gene leads to a temperature-sensitive failure of meiosis in late Zygotene/Pachytene that is associated with defective formation of the synaptonemal complex, reduced bivalent formation and crossing over, and aneuploid gametes. An aphenotypic insertion in the cyclin L gene, a cognate cyclin for CDKG, strongly enhances the phenotype of cdkg1-1 mutants, indicating that this cdk-cyclin complex is essential for male meiosis. Since CYCLINL, CDKG, and their mammalian homologs have been previously shown to affect mRNA processing, particularly alternative splicing, our observations also suggest a mechanism to explain the widespread phenomenon of thermal sensitivity in male meiosis.
John Innes Centre, Norwich NR4 7UH, United Kingdom.
Tao
T
Zheng
Candida
C
Nibau
Dylan W
DW
Phillips
Glyn
G
Jenkins
Susan J
SJ
Armstrong
John H
JH
Doonan
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000502:physiology*; D023902:Chromosome Pairing / Q000502:physiology*; D032461:Chromosomes, Plant; D006358:Hot Temperature; D011058:Pollen; D016133:Polymerase Chain Reaction; D011494:Protein Kinases / Q000378:metabolism*
D029681:Arabidopsis Proteins; D011494:Protein Kinases