AtTCP16, a class I TCP transcription factor, regulates the expression of SAM-related genes.

UBERTI MANASSERO, NG; GONZÁLEZ, DH

Mendoza

Congreso; XLVII Reunión Anual Sociedad Argentina de Investigación en Bioquímica y Biología Molecular; 2011

Sociedad Argentina de Investigación en Bioquímica y Biología Molecular (SAIB)

TCP-domain proteins constitute a family of transcription factors found only in plants. They can be divided into two classes and are generally involved in the regulation of cell growth and proliferation. In order to analyze the role of class I TCP transcription factors, we transformed Arabidopsis plants with a construct that express AtTCP16 fused to the EAR repressor domain under the control of the 35SCaMV promoter. After the first kanamycin selection, 30% of the plants show adventitious meristems (AM) in the intersection of the cotyledon vascular elements. Those AM develop as a functional SAM, both maintaining an undifferentiated pool of cells expressing STM, KNAT1 and CLV3 and promoting lateral organ formation. Even more interesting, a complete plant whit rosette leaves, inflorescence and siliques is generated from each AM. The ectopic  expression of 35S::TCP16-EAR in stm mutant background diminish the appearance of AM to a 7%, demonstrating that STM ectopic activation it is necessary for the AM formation. These observations suggest that AtTCP16 is involved in the fine regulation of the spatio-temporal control of meristem specific genes, probably mediated by the STM patway.