Disease relevance of Cnx99A

• Finally, mutations in calnexin lead to retinal degeneration that is enhanced by light, suggesting that calnexin's function as a Ca2+ buffer is important for photoreceptor cell survival [1].

High impact information on Cnx99A

• A 90-kilodalton membrane-bound chaperone of the endoplasmic reticulum (ER), termed calnexin, associates quantitatively with newly synthesized class I heavy chains, but the functions of calnexin in this interaction are unknown [2].
• Mutations in calnexin also impair the ability of photoreceptor cells to control cytosolic Ca2+ levels following activation of the light-sensitive TRP channels [1].
• Calnexin is essential for rhodopsin maturation, Ca2+ regulation, and photoreceptor cell survival [1].
• Our results illustrate a critical role for calnexin in Rh1 maturation and Ca2+ regulation and provide genetic evidence that defects in calnexin lead to retinal degeneration [1].
• The deduced amino acid sequence shares several regions of homology with Cnx from other sources with two conserved motifs each repeated four times [3].

Biological context of Cnx99A

• Nucleotide sequence of a Drosophila melanogaster cDNA encoding a calnexin homologue [3].
• In addition, we will describe insect and mammalian expression systems in which major histocompatibility complex class I molecules are used as model glycoprotein substrates for CNX and CRT [4].
• In vitro and in vivo assays to assess the functions of calnexin and calreticulin in ER protein folding and quality control [4].

References