3 research outputs found
Dissecting the function of Atg1 complex in Dictyostelium autophagy reveals a connection with the pentose phosphate pathway enzyme transketolase
The network of protein–protein interactions of the Dictyostelium discoideum
autophagy pathway was investigated by yeast two-hybrid screening of the
conserved autophagic proteins Atg1 and Atg8. These analyses confirmed
expected interactions described in other organisms and also identified
novel interactors that highlight the complexity of autophagy regulation.
The Atg1 kinase complex, an essential regulator of autophagy, was investigated
in detail here. The composition of the Atg1 complex in D. discoideum is
more similar to mammalian cells than to Saccharomyces cerevisiae as, besides
Atg13, it contains Atg101, a protein not conserved in this yeast. We found
that Atg101 interacts with Atg13 and genetic disruption of these proteins
in Dictyostelium leads to an early block in autophagy, although the severity
of the developmental phenotype and the degree of autophagic block is
higher in Atg13-deficient cells. We have also identified a protein containing
zinc-finger B-box and FNIP motifs that interacts with Atg101. Disruption of
this protein increases autophagic flux, suggesting that it functions as a negative
regulator of Atg101.We also describe the interaction of Atg1 kinase with
the pentose phosphate pathway enzyme transketolase (TKT). We found
changes in the activity of endogenous TKT activity in strains lacking or
overexpressing Atg1, suggesting the presence of an unsuspected regulatory
pathway between autophagy and the pentose phosphate pathway in
Dictyostelium that seems to be conserved in mammalian cellsThis work was supported by grant nos. BFU2009-09050 and
BFU2012-32536 from the Spanish Ministerio de EconomÃa y competitividad.
The cost of this publication has been paid in part by FEDER
funds. A.M. was recipient of a predoctoral fellowship (FPI associated
to the grant no. BFU2012-32536). L.C.T. is recipient of a FPU fellowship
from Ministerio de Educación, cultura y deport
Dissecting the function of Atg1 complex in Dictyostelium autophagy reveals a connection with the pentose phosphate pathway enzyme transketolase
The network of protein-protein interactions of the Dictyostelium discoideum autophagy pathway was investigated by yeast two-hybrid screening of the conserved autophagic proteins Atg1 and Atg8. These analyses confirmed expected interactions described in other organisms and also identified novel interactors that highlight the complexity of autophagy regulation. The Atg1 kinase complex, an essential regulator of autophagy, was investigated in detail here. The composition of the Atg1 complex in D. discoideum is more similar to mammalian cells than to Saccharomyces cerevisiae as, besides Atg13, it contains Atg101, a protein not conserved in this yeast. We found that Atg101 interacts with Atg13 and genetic disruption of these proteins in Dictyostelium leads to an early block in autophagy, although the severity of the developmental phenotype and the degree of autophagic block is higher in Atg13-deficient cells. We have also identified a protein containing zinc-finger B-box and FNIP motifs that interacts with Atg101. Disruption of this protein increases autophagic flux, suggesting that it functions as a negative regulator of Atg101. We also describe the interaction of Atg1 kinase with the pentose phosphate pathway enzyme transketolase (TKT). We found changes in the activity of endogenous TKT activity in strains lacking or overexpressing Atg1, suggesting the presence of an unsuspected regulatory pathway between autophagy and the pentose phosphate pathway in Dictyostelium that seems to be conserved in mammalian cells.This work was supported by grant nos. BFU2009-09050 and BFU2012-32536 from the Spanish Ministerio de EconomÃa y competitividad. The cost of this publication has been paid in part by FEDER funds. A.M. was recipient of a predoctoral fellowship (FPI associated to the grant no. BFU2012-32536). L.C.T. is recipient of a FPU fellowship from Ministerio de Educación, cultura y deporte.Peer Reviewe