Differential distribution of xyloglucan glycosyl transferases in pea Golgi dictyosomes and secretory vesicles

摘要: Rate-zonal centrifugation of pea ( Pisum sativum var. Alaska) stem microsomal membranes on a linear Renografln gradient separated Golgi secretory vesicles from dictyosomes. Secretory possessed high levels xyloglucan fucosyl transferase activity, which effects the final decoration side-chains, but lacked substantial xylosyl is required for synthesis backbone. In contrast, total dictyosomal both and activities. Isopycnic homogenized dictyosome-enriched membrane preparation shallower indicated that lighter relatively little activity. The bulk formed denser peak in activities codistributed. Thus differential localization function apparatus during biosynthesis indicated. A tentative mechanism suggested elaboration glucose-xylose backbone initiated membranes, concluded fucosylation begun completed transport to cell wall.