OsTSD2Gene Is Involved In Root Development In A ABA-Dependent Manner

Root development is the key stage in plant life cycle and also is the starting point for much important crop production. Rice OsTSD2(Tumorous Shoot Development) genes,which is a possible methyltransferase, is involved in the synthesis of pectin.With a low concentration of ABA treatment, rice OsTSD2gene of T-DNA insertion mutant seedlings showed primary root growth inhibition and increased lateral root density and swelling of root tip. Acid polypeptide of OsTSD2containing a single membrane-spanning domain in the N-terminal part and a methyltransferase domains. Prediction of OsTSD2was predicted to be localized in Golgi appraratus. Being compared to the wild type, Ostsd2mutants were more sensitivity to ABA, expression of ABA-related pathway genes were upregulated by ABA, ABA content was increased, aerenchyma formation mode was different, cell adhesion was reduced,pectin methylation was changed and uronic acid content was reduced. Expression of a TSD2:GUS reporter gene was detected mainly in root tip, Lateral root primordial and column.This findings clearly indicated that Ostsd2gene was a possible pectin methyltransferase, which combined with ABA to affect pectin and pectin methyl level. Ostsd2may play an essential role to pectin and root development.