Measuring piecemeal microautophagy of the nucleus in Saccharomyces cerevisiae.

Piecemeal microautophagy of the nucleus (PMN) selectively removes and degrades small fragments of the Saccharomyces cerevisiae nucleus. Interorganelle contact sites called nucleus-vacuole (NV) junctions determine the selectivity of PMN by establishing a platform for the biogenesis of PMN blebs and vesicles. PMN structures can be observed by fluorescence microscopy using GFP-tagged reporters; however, this approach is best supported with quantitative immunoblot assays of PMN-specific cargo degradation. Together, these assays should facilitate the further study of this fascinating but poorly understood autophagic process in different genetic backgrounds, physiological states, and environmental conditions.