The necessity of nucleophagic modality.

Nucleophagy, the selective subtype of autophagy that predominantly targets only a selected and (nonessential) portion of the nucleus, and rarely the nucleus in its entirety, for degradation, reinforces the paradigm that nucleophagy recycling is a meticulous and highly delicate process guarded by fail-safe mechanisms. Our goal in this commentary is to encourage autophagy researchers and other scientists to explore nucleophagy blind spots and gain advanced insights into the diverse roles of this process and its selective modality as they pertain to intranuclear quality control and cellular homeostasis. Identifying and deciphering nucleophagic signaling, regulation, molecular mechanism(s) and its mediators, cargo composition and nuclear membrane dynamics under numerous physiological and/or pathological settings will provide important advances in our understanding of this critical type of organelle-selective autophagy.Abbreviations: INM, inner nuclear membrane; LN, late nucleophagy; mRNA, messenger RNA; NE, nuclear envelope; NL, nuclear lamina; NPC(s), nuclear pore complex(es); NVJ(s), nucleus-vacuole junction(s); ONM, outer nuclear membrane; PMN, piecemeal microautophagy of the nucleus; PND, programmed nuclear death; PNuD, programmed nuclear destruction; rDNA/rRNA, ribosomal DNA/RNA.