A double-negative feedback loop between miR319c and JAW-TCPs establishes growth pattern in incipient leaf primordia in Arabidopsis thaliana.

The microRNA miR319 and its target JAW-TCP transcription factors regulate the proliferation-to-differentiation transition of leaf pavement cells in diverse plant species. In young Arabidopsis leaf primordia, JAW-TCPs are detected towards the distal region whereas the major mRNA319-encoding gene MIR319C, is expressed at the base. Little is known about how this complementary expression pattern of MIR319C and JAW-TCPs is generated.

The TCP4 Transcription Factor Directly Activates and and Suppresses Trichome Initiation.

Trichomes are the first line of defense on the outer surface of plants against biotic and abiotic stresses. Because trichomes on leaf surfaces originate from the common epidermal progenitor cells that also give rise to pavement cells and stomata, their density and distribution are under strict genetic control. Regulators of trichome initiation have been identified and incorporated into a biochemical pathway wherein an initiator complex promotes trichome fate in an epidermal progenitor cell, while an inhibitor complex suppresses it in the neighboring cells.

Generation of Inducible Transgenic Lines of Arabidopsis Transcription Factors Regulated by MicroRNAs.

Transcription factors play key regulatory roles in all the life processes across kingdoms. In plants, the genome of a typical model species such as Arabidopsis thaliana encodes over 1500 transcription factors that regulate the expression dynamics of all the genes in time and space. Therefore, studying their function by analyzing the loss and gain-of-function lines is of prime importance in basic plant biology and its agricultural application.