The Formation of Buds in Yeast

SUMMARY: Vesicles accumulate at the site of bud formation in the mother cell and are also found in the growing bud during the growth of its wall. The bud is in direct communication with the mother cell until maturity when a septum which is formed across the cytoplasm grows inwards from the wall and is subsequently thickened on both sides. During the thickening process vesicles are present at both surfaces of the cross-wall which finally has two layers one of which becomes continuous with the bud cell wall. It is suggested that the vesicles carry material both into the growing bud wall and into the septum.