Calreticulin (mutant) (CALR)

Mutant Calreticulin (CALR) is a mutated form of the calreticulin protein, most commonly found in myeloproliferative neoplasms (MPNs) like essential thrombocythemia and primary myelofibrosis, particularly in patients lacking JAK2 or MPL mutations. The mutations, usually insertions or deletions in exon 9, lead to a frameshift and a novel positively charged C-terminal sequence without the KDEL motif. This altered protein constitutively activates the thrombopoietin receptor MPL/TpoR, leading to persistent JAK/STAT signaling and abnormal cell proliferation. Mutant CALR can be targeted by immunotherapies.

Other names

Mutant Calreticulin

Disrupting mutant CALR interaction with TpoR/MPL