Characterization of the three Arabidopsis thaliana RAD21 cohesins reveals differential responses to ionizing radiation.
The RAD21/REC8 gene family has been implicated in sister chromatid cohesion and DNA repair in several organisms. Unlike most eukaryotes, Arabidopsis thaliana has three RAD21 gene homologues, and their cloning and characterization are reported here. All three genes, AtRAD21.1, AtRAD21.2, and AtRAD21.3, are expressed in tissues rich in cells undergoing cell division, and AtRAD21.3 shows the highest relative level of expression. An increase in steady-state levels of AtRAD21.1 transcript was also observed, specifically after the induction of DNA damage. Phenotypic analysis of the atrad21.1 and atrad21.3 mutants revealed that neither of the single mutants was lethal, probably due to the redundancy in function of the AtRAD21 genes. However, AtRAD21.1 plays a critical role in recovery from DNA damage during seed imbibition, prior to germination, as atrad21.1 mutant seeds are hypersensitive to radiation damage.
Department of Plant Sciences, University of Oxford, South Parks Road, Oxford OX1 3RB, UK.
J A
JA
da Costa-Nunes
A M
AM
Bhatt
S
S
O'Shea
C E
CE
West
C M
CM
Bray
U
U
Grossniklaus
H G
HG
Dickinson
D017360:Arabidopsis / Q000235:genetics* / Q000502:physiology / Q000528:radiation effects*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D003001:Cloning, Molecular; D004249:DNA Damage; D035264:Flowers / Q000033:anatomy & histology / Q000502:physiology / Q000528:radiation effects; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D009154:Mutation; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D010641:Phenotype; D012333:RNA, Messenger / Q000378:metabolism; D011839:Radiation, Ionizing; D036226:Seedlings / Q000033:anatomy & histology / Q000502:physiology / Q000528:radiation effects; D012639:Seeds / Q000033:anatomy & histology / Q000502:physiology / Q000528:radiation effects; D020539:Sequence Analysis, Protein; D012689:Sequence Homology, Nucleic Acid; D018797:Cell Cycle Proteins
D029681:Arabidopsis Proteins; D002868:Chromosomal Proteins, Non-Histone; D009687:Nuclear Proteins; D012333:RNA, Messenger; C510670:RAD21.2 protein, Arabidopsis; C510671:RAD21.3 protein, Arabidopsis; C432544:SYN2 protein, Arabidopsis; D018797:Cell Cycle Proteins