STRINGSTRING
KAR2 protein (Saccharomyces cerevisiae) - STRING interaction network
"KAR2" - ATPase involved in protein import into the ER, also acts as a chaperone to mediate protein folding in the ER and may play a role in ER export of soluble proteins in Saccharomyces cerevisiae
Nodes:
Network nodes represent proteins
splice isoforms or post-translational modifications are collapsed, i.e. each node represents all the proteins produced by a single, protein-coding gene locus.
Node Color
colored nodes:
query proteins and first shell of interactors
white nodes:
second shell of interactors
Node Content
empty nodes:
proteins of unknown 3D structure
filled nodes:
some 3D structure is known or predicted
Edges:
Edges represent protein-protein associations
associations are meant to be specific and meaningful, i.e. proteins jointly contribute to a shared function; this does not necessarily mean they are physically binding each other.
Known Interactions
from curated databases
experimentally determined
Predicted Interactions
gene neighborhood
gene fusions
gene co-occurrence
Others
textmining
co-expression
protein homology
Your Input:
Neighborhood
Gene Fusion
Cooccurence
Coexpression
Experiments
Databases
Textmining
[Homology]
Score
KAR2ATPase involved in protein import into the ER, also acts as a chaperone to mediate protein folding in the ER and may play a role in ER export of soluble proteins; regulates the unfolded protein response via interaction with Ire1p; Probably plays a role in facilitating the assembly of multimeric protein complexes inside the ER. Is required for secretory polypeptide translocation. May physically associate with SEC63 protein in the endoplasmic reticulum and this interaction may be regulated by ATP hydrolysis (682 aa)    
Predicted Functional Partners:
SCJ1
One of several homologs of bacterial chaperone DnaJ, located in the ER lumen where it cooperates with Kar2p to mediate maturation of proteins; Regulates protein folding in the endoplasmic reticulum lumen. Probably acts as a J-protein for the Hsp70-type chaperone KAR2 by stimulating its ATP-dependent reaction cycle and initiating folding reactions. Also involved in the endoplasmic reticulum-associated degradation (ERAD) process. Cooperates with KAR2 and another J-protein JEM1 to facilitate the export of ERAD substrates to the cytoplasm by maintaining them in a translocation-competent st [...] (377 aa)
 
  0.999
SIS1
Type II HSP40 co-chaperone that interacts with the HSP70 protein Ssa1p; not functionally redundant with Ydj1p due to due to substrate specificity; shares similarity with bacterial DnaJ proteins; Required for nuclear migration during mitosis. It is required for the normal initiation of translation. Might mediate the dissociation of a specific protein complex of the translation machinery. Essential for viability (352 aa)
 
  0.998
YDJ1
Type I HSP40 co-chaperone involved in regulation of the HSP90 and HSP70 functions; involved in protein translocation across membranes; member of the DnaJ family; Probably involved in mitochondrial protein import. Is also required for efficient translocation of pre-pro-alpha-factor. Involved in heme regulation of HAP1, as a component of the high- molecular-weight (HMC) complex (409 aa)
 
  0.997
HSP82
Hsp90 chaperone required for pheromone signaling and negative regulation of Hsf1p; docks with Tom70p for mitochondrial preprotein delivery; promotes telomerase DNA binding and nucleotide addition; interacts with Cns1p, Cpr6p, Cpr7p, Sti1p; Molecular chaperone that promotes the maturation, structural maintenance and proper regulation of specific target proteins involved in cell cycle control and signal transduction. Undergoes a functional cycle that is linked to its ATPase activity. The nucleotide-free form of the dimer is found in an open conformation in which the N-termini are not dim [...] (709 aa)
     
 
  0.996
PDI1
Protein disulfide isomerase; multifunctional protein resident in the endoplasmic reticulum lumen, essential for the formation of disulfide bonds in secretory and cell-surface proteins, unscrambles non-native disulfide bonds; forms a complex with Mnl /.../t has exomannosidase activity, processing unfolded protein-bound Man8GlcNAc2 oligosaccharides to Man7GlcNAc2 which promotes degradation in the unfolded protein response; Protein disulfide isomerase of ER lumen required for formation of disulfide bonds in secretory and cell-surface proteins and which unscrambles non-native disulfide bon [...] (522 aa)
   
 
  0.995
SEC63
Essential subunit of Sec63 complex (Sec63p, Sec62p, Sec66p and Sec72p); with Sec61 complex, Kar2p/BiP and Lhs1p forms a channel competent for SRP-dependent and post-translational SRP-independent protein targeting and import into the ER; Acts as component of the Sec62/63 complex which is involved in SRP-independent post-translational translocation across the endoplasmic reticulum (ER) and functions together with the Sec61 complex and KAR2 in a channel-forming translocon complex. A cycle of assembly and disassembly of Sec62/63 complex from SEC61 may govern the activity of the translocon. [...] (663 aa)
     
 
  0.994
HRD3
ER membrane protein that plays a central role in ERAD; forms HRD complex with Hrd1p and ER-associated protein degradation (ERAD) determinants that engages in lumen to cytosol communication and coordination of ERAD events; Component of the endoplasmic reticulum quality control (ERQC) system involved in ubiquitin-dependent degradation of missfolded endoplasmic reticulum proteins. Component of the HRD1 ubiquitin ligase complex, which is part of the ERAD-L and ERAD-M pathways responsible for the rapid degradation of soluble lumenal and membrane proteins with misfolded lumenal domains (ERAD [...] (833 aa)
       
  0.993
HSC82
Cytoplasmic chaperone of the Hsp90 family, redundant in function and nearly identical with Hsp82p, and together they are essential; expressed constitutively at 10-fold higher basal levels than HSP82 and induced 2-3 fold by heat shock; Molecular chaperone that promotes the maturation, structural maintenance and proper regulation of specific target proteins involved in cell cycle control and signal transduction such as CNA2. Undergoes a functional cycle that is linked to its ATPase activity (By similarity). Interacts dynamically with various co-chaperones that modulate its substrate reco [...] (705 aa)
     
 
  0.993
IRE1
Serine-threonine kinase and endoribonuclease; transmembrane protein that mediates the unfolded protein response (UPR) by regulating Hac1p synthesis through HAC1 mRNA splicing; Kar2p binds inactive Ire1p and releases from it upon ER stress; Senses unfolded proteins in the lumen of the endoplasmic reticulum via its N-terminal domain which leads to enzyme auto- activation. The active endoribonuclease domain splices HAC1 precursor mRNA to produce the mature form which then induces transcription of UPR target genes (1115 aa)
       
 
  0.992
UBI4
Ubiquitin, becomes conjugated to proteins, marking them for selective degradation via the ubiquitin-26S proteasome system; essential for the cellular stress response; encoded as a polyubiquitin precursor comprised of 5 head-to-tail repeats; Ubiquitin exists either covalently attached to another protein, or free (unanchored). When covalently bound, it is conjugated to target proteins via an isopeptide bond either as a monomer (monoubiquitin), a polymer linked via different Lys residues of the ubiquitin (polyubiquitin chains) or a linear polymer linked via the initiator Met of the ubiqui [...] (381 aa)
     
  0.992
Your Current Organism:
Saccharomyces cerevisiae
NCBI taxonomy Id: 4932
Other names: Candida robusta, Pachytichospora, S. cerevisiae, Saccharomyces, Saccharomyces capensis, Saccharomyces cerevisiae, Saccharomyces italicus, Saccharomyces oviformis, Saccharomyces uvarum var. melibiosus, lager beer yeast, yeast
Server load: low (3%) [HD]