Old factors, new players: transcriptional regulation of autophagy

Abstract

Macroautophagy/autophagy is a catabolic process that allows cells to adapt to environmental changes and maintain energy homeostasis. This multistep process is regulated at several levels, including transcriptionally regulating autophagy-related (<i>ATG</i>) gene expression through the action of transcription regulators. Very recently, Wen et al. and we have provided more evidence that two well-known transcription factors regulate different <i>ATG</i> genes to control either nonselective or selective forms of autophagy, respectively. Under nitrogen-starvation conditions, the Spt4-Spt5 complex derepresses <i>ATG8</i> and <i>ATG41</i> expression and upregulates bulk autophagy activity. By contrast, under glucose-starvation conditions, the Paf1 complex (the polymerase-associated factor 1 complex, Paf1C) specifically modulates expression of <i>ATG11</i> and <i>ATG32</i> to regulate mitophagy. These studies suggest the potential existence of other transcription regulators yet to be discovered that function in the regulation of diverse autophagy pathways.<b>Abbreviations</b>: AMPK: AMP-activated protein kinase; ATG: autophagy-related; NELF: negative elongation factor; Paf1C/PAF1C: polymerase-associated factor 1 complex; RNAP II: RNA polymerase II; Rpd3L: Rpd3 large complex.