Cellular material that is destined for degradation is enclosed by a double-membraned vesicle during the process of autophagy. The resulting autophagosome matures and fuses with lysosomes to complete cargo degradation. Besides quality control, autophagy is a response pathway to stresses such as starvation, during which autophagosomes are formed. However, it is unknown whether the later stages of mammalian autophagosome maturation and lysosome fusion are regulated by starvation. In their Research Article (Kuchitsu et al., 2018), Naonobu Fujita, Mitsunori Fukuda and co-workers address this using a knockout cell line for the small GTPase Rab7, known to be required for autophagy in several model organisms. The authors demonstrate that absence of Rab7 causes accumulation of autolysosomes, but not autophagosomes, in fed conditions. Interestingly, a brief starvation of the cells led to clearance of these autolysosomes. This is dependent on the presence of glutamine and, in addition, autolysosome maturation is also observed in starved wild-type cells. Thus, Rab7 is dispensable for mammalian autophagosome–lysosome fusion, which is a process that is regulated by starvation. Furthermore, this process is independent of the central autophagy regulator mammalian target of rapamycin complex 1 (mTORC1). This study highlights a new concept of a general regulation of autolysosome maturation by nutrient starvation in mammals.
Starvation controls late autophagy steps
- Split-screen
- Views Icon Views
-
Article Versions Icon
Versions
- Version of Record 06 April 2018
- Share Icon Share
-
Tools Icon
Tools
- Search Site
Starvation controls late autophagy steps. J Cell Sci 1 April 2018; 131 (7): e0701. doi:
Download citation file:
Advertisement
Cited by
JCS Journal Meeting 2023: Imaging Cell Dynamics

Our 2023 Journal Meeting on ‘Imaging Cell Dynamics’ will be held from 14-17 May 2023 in Lisbon, Portugal. We have a limited number of spaces left so sign up now! Registration deadline: 31 March.
Call for papers: Cell and Tissue Polarity
-PolarityCFP.png?versionId=4491)
We are welcoming submissions for our next special issue, which will focus on ‘Cell and tissue polarity’ and will be guest edited by David Bryant. Submission deadline: 15 July.
Webinar: Increasing the visibility and impact of your research
-HUBSwebinar.jpg?versionId=4491)
Would you like to increase the visibility and impact of your research and raise your profile internationally? If so, register for the very practical webinar we are running in association with HUBS on 23 February 2023.
Cell scientist to watch: Gautam Dey

We interviewed Gautam Dey, who became a group leader at EMBL in Heidelberg, Germany, in 2021. His lab investigates the fundamental organisational principles and evolutionary dynamics of the nuclear compartment across eukaryotes.
Mechanisms of eukaryotic transcription termination at a glance

Check out our latest Cell Science at a Glance article and accompanying poster for an overview of the current understanding about the mechanisms of transcription termination by the three eukaryotic RNAPs.