672 / 2019-04-30 16:15:39

SNX1 is a novel endomembrane regulator of shade response

SNX1, retromer complex，shade avoidance response

全体主题 > Cell Biology

Light plays a vital role in multiple plant developmental processes. When grown in shade condition, plants can perceive the reduced R/FR ratio by phytochrome photoreceptors and trigger a series of developmental responses known as shade avoidance response. The most dramatic response to shade is the stimulation of hypocotyl elongation which is often associated with impaired root growth. The mechanism of how shade promotes hypocotyl elongation is well studied. However, the reason why root growth is impaired under shade is poorly understood. Retromer complex is a conserved complex in eukaryotic cells. It is composed of two subcomplexes, the SNX dimer (SNX1 and SNX2) and the retromer core (VPS29,VPS26 and VPS35). Here we show that snx1, a mutant of key subunit of retromer complex, had longer root when grown in shade condition compared with wild type，while the retromer core mutants exhibited normal response. We further showed that shade stimulus reduced the endosomal distribution of SNX1 but not VPS29, implying that the two subcomplexes may have functional differentiation in shade condition. Two candidate cargos of the retromer complex, PIN2 and BRI1, were translocated to vacuole lumen in response to shade stimulus. Therefore, we propose that SNX1 is an important endomembrane factor that could sense the shade stimulus and regulate root growth through the change of subcellular localization and cargo selection.