Plant Genomics

Biography

Biography: Xia Li

Abstract

The        stem cell        niche in the root meris tem maintains       pluripotent stem cells       to ensure a  constant supply of cells for       root growth      . Despite extensive progress, the      molecular mechanisms      through which root     stem cell     fa   tes and     stem cell     niche activity are determined remain lar gely unknown. In    Arabidopsis    thaliana, the Pl eiotropic Regulatory Locus 1 (PRL1) encodes a WD40-repeat protein subunit  of the spliceosome-activating Nineteen complex (NTC) that plays a role in multiple stress, hormone and    developmental signaling pathways   . In this study, we show that   PRL1   is involved in the control of  root meristem  size and root stem cell     niche activity. PRL1 is strongly expressed in the root meristem and its loss of function mutation results in disorganization of the quiescent center (QC),  premature stem cell  differentiation,  aberrant cell division , a nd reduced root meristem size. O ur genetic studies indicate that PRL1 is required for confined expression of the homeodomain  tran scription  factor WOX5 in the QC and acts upstream of the transcription factor PLETHORA (PLT) in mo dulating stem cell niche ac tivity and root meristem size. These findings define a role for PRL1 as an important determinant of PLT signaling that modulates maintenance of the stem c ell niche and root meristem size.