PMID- 32116088
OWN - NLM
STAT- MEDLINE
DCOM- 20211203
LR  - 20240503
IS  - 1554-8635 (Electronic)
IS  - 1554-8627 (Print)
IS  - 1554-8627 (Linking)
VI  - 17
IP  - 3
DP  - 2021 Mar
TI  - The proppin Bcas3 and its interactor KinkyA localize to the early phagophore and 
      regulate autophagy.
PG  - 640-655
LID - 10.1080/15548627.2020.1725403 [doi]
AB  - To resolve the signaling mechanisms that mediate the starvation-induced processes 
      of Dictyostelium sporulation and encystation, we performed insertional 
      mutagenesis on cells harboring an mRFP-tagged spore gene. We isolated a mutant in 
      kinkyA (knkA), a gene without known function, which formed fruiting bodies with a 
      kinked stalk and lacking viable spores. Immunoprecipitation of lysates of 
      KnkA-YFP-transformed knkA(-) cells yielded a mammalian BCAS3 homolog as a KnkA 
      interactor. bcas3(-) phenocopied knkA(-) and Bcas3 colocalized with KnkA to 
      puncta. Bcas3 shares sequence similarity with proppins (beta-propellors that bind 
      phosphoinositides). Mutation of 2 Bcas3 residues that are essential for PtdIns3P 
      binding in proppins prevented Bcas3 binding to PtdIns3P as well as punctate Bcas3 
      and KnkA localization. KnkA puncta also colocalized with small but not large 
      vesicles that contain the autophagy protein Atg8 and were contiguous with the 
      endoplasmic reticulum. knkA(-) and bcas3(-) cells showed a pronounced decrease of 
      RFP-GFP-Atg8 in neutral early autophagosomes, indicating that KnkA and Bcas3 are 
      required for macroautophagy/autophagy. Knockouts in atg7, atg5 or atg9 
      substantiated this finding by showing similar sporulation defects as knkA(-) and 
      bcas3(-). Defective Dictyostelium sporulation is evidently a useful diagnostic 
      tool for the discovery of novel autophagy genes.Abbreviations: Atg: 
      Autophagy-related; BCAS3: BCAS3 microtubule associated cell migration factor; 
      cAMP: 3',5'-cyclic adenosine monophosphate; ER: endoplasmic reticulum; GFP: green 
      fluorescent protein; PAS: phagophore assembly site; PRKA/PKA: protein kinase 
      cAMP-dependent; Proppin: beta-propellers that bind phosphoinositides; PtdIns3P: 
      phosphatidylinositol 3-phosphate; REMI: restriction enzyme-mediated insertional 
      mutagenesis; RFP: red fluorescent protein; RT-qPCR: reverse transcriptase - 
      quantitative polymerase chain reaction; WIPI: WD repeat domain, phosphoinositide 
      interacting; YFP: yellow fluorescent protein.
FAU - Yamada, Yoko
AU  - Yamada Y
AD  - School of Life Sciences, University of Dundee, Dundee, UK.
AD  - Department of Biology, Faculty of Science, Toho University, Funabashi, Japan.
FAU - Schaap, Pauline
AU  - Schaap P
AUID- ORCID: 0000-0003-4500-2555
AD  - School of Life Sciences, University of Dundee, Dundee, UK.
LA  - eng
GR  - WT_/Wellcome Trust/United Kingdom
GR  - 100293/Z/12/Z/WT_/Wellcome Trust/United Kingdom
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20200301
PL  - United States
TA  - Autophagy
JT  - Autophagy
JID - 101265188
RN  - 0 (Autophagy-Related Proteins)
RN  - 0 (Membrane Proteins)
RN  - 147336-22-9 (Green Fluorescent Proteins)
SB  - IM
MH  - Animals
MH  - Autophagosomes/*genetics/metabolism
MH  - Autophagy/*genetics/physiology
MH  - Autophagy-Related Proteins/metabolism
MH  - Dictyostelium/*genetics/metabolism
MH  - Endoplasmic Reticulum/*metabolism
MH  - Green Fluorescent Proteins/metabolism
MH  - Membrane Proteins/metabolism
MH  - Phagosomes/metabolism
PMC - PMC8032249
OTO - NOTNLM
OT  - Atg8 processing
OT  - Dictyostelium
OT  - Knka
OT  - breast carcinoma amplified sequence 3
OT  - inositol phospholipid binding
OT  - phagophore assembly
COIS- No potential conflict of interest was reported by the authors.
EDAT- 2020/03/03 06:00
MHDA- 2021/12/15 06:00
PMCR- 2020/03/01
CRDT- 2020/03/03 06:00
PHST- 2020/03/03 06:00 [pubmed]
PHST- 2021/12/15 06:00 [medline]
PHST- 2020/03/03 06:00 [entrez]
PHST- 2020/03/01 00:00 [pmc-release]
AID - 1725403 [pii]
AID - 10.1080/15548627.2020.1725403 [doi]
PST - ppublish
SO  - Autophagy. 2021 Mar;17(3):640-655. doi: 10.1080/15548627.2020.1725403. Epub 2020 
      Mar 1.