CANX

Function

Calcium-binding protein that interacts with newly synthesized glycoproteins in the endoplasmic reticulum. It may act in assisting protein assembly and/or in the retention within the ER of unassembled protein subunits. It seems to play a major role in the quality control apparatus of the ER by the retention of incorrectly folded proteins. Associated with partial T-cell antigen receptor complexes that escape the ER of immature thymocytes, it may function as a signaling complex regulating thymocyte maturation. Additionally it may play a role in receptor-mediated endocytosis at the synapse.

Post-translational modifications

Phosphorylated at Ser-564 by MAPK3/ERK1. phosphorylation by MAPK3/ERK1 increases its association with ribosomes (By similarity).

Palmitoylation by DHHC6 leads to the preferential localization to the perinuclear rough ER. It mediates the association of calnexin with the ribosome-translocon complex (RTC) which is required for efficient folding of glycosylated proteins.

Ubiquitinated, leading to proteasomal degradation. Probably ubiquitinated by ZNRF4.

Sequence similarities

Belongs to the calreticulin family.

Cellular localization

• Endoplasmic reticulum membrane
• Single-pass type I membrane protein
• Endoplasmic reticulum
• Melanosome
• Identified by mass spectrometry in melanosome fractions from stage I to stage IV (PubMed:12643545, PubMed:17081065). The palmitoylated form preferentially localizes to the perinuclear rough ER (PubMed:22314232).

Alternative names

• Calnexin
• IP90
• Major histocompatibility complex class I antigen-binding protein p88
• p90
• CANX

Database links

• entrezGene:821
• omim:114217
• swissprot:P27824

Target type

Proteins

Primary research area

Oncology

Other research areas

• Neuroscience

Molecular weight

67568Da