Abstract
Meristem keeps supplying cells to organs while maintaining its defined structure. tebichee (teb) mutant of Arabidopsis is defective in meristem structure and shows abnormal organ shape. TEB gene encodes a homolog of MUS308 of Drosohila, which is involved in repair and response to DNA damage. In teb plants, expression levels of genes inducible by DNA doublestrand-breaks were higher than the wild type. In addition more cells in meristems of teb expressed cyclinB1::GUS than those in the wild type, suggesting that defect in cell cycle progression leads to meristem disorganization in teb. Double mutant of teb and atr-2, which has a mutation in ATR involved in DNA replication checkpoint, showed enhanced phenotypes of teb, suggesting that TEB is involved in progression of DNA replication and/or checkpoint mechanism. Further functional analysis of TEB will reveal a relationship between the DNA replication or cell cycle regulation and the structure of meristems and organs.
