Disease relevance of crt-1

• Comparison of the C. elegans sequence with the calreticulin-related antigen RAL-1 of Oncocerca volvulus shows 73% identity, excluding the calreticulin C-terminal region [1].
• The striking similarity of the parasite Ag and the human autoantigen has led to the hypothesis that RAL1 may induce a cross-reactive immune response to calreticulin, which in turn may be involved in the pathogenesis of onchocerciasis [2].

High impact information on crt-1

• In C. elegans CRT-1 is expressed in the intestine, pharynx, body-wall muscles, head neurons, coelomocytes, and in sperm. crt-1 males exhibit reduced mating efficiency and defects late in sperm development in addition to defects in oocyte development and/or somatic gonad function in hermaphrodites [3].
• Calreticulin (CRT), a Ca(2+)-binding protein known to have many cellular functions, including regulation of Ca(2+) homoeostasis and chaperone activity, is essential for heart and brain development during embryogenesis in mice [3].
• Epitopes of the Onchocerca volvulus RAL1 antigen, a member of the calreticulin family of proteins, recognized by sera from patients with onchocerciasis [2].
• Here, we describe the application of RNA interference (RNAi) to the root-knot nematode Meloidogyne incognita for the knock-down of two genes expressed in the subventral esophageal glands of the nematode and potentially involved in parasitism, the calreticulin (Mi-crt) and the polygalacturonase (Mi-pg-1) genes [4].
• Moreover, a double knockout mutant of calnexin and calreticulin exhibits additive severe defects [5].

Biological context of crt-1

• The C. elegans gene described here and designated crt-1 was mapped to a region towards the left-hand end of Chromosome V on the physical map of the genome [1].
• The gene encoding a C. elegans homologue of the mammalian reticuloplasmin, calreticulin, was cloned and sequenced and the amino-acid sequence of its product deduced [1].

Anatomical context of crt-1

• Suppression was also achieved by mutation in calreticulin, which is necessary for maintainance of intracellular Ca2+ stores in the endoplasmic reticulum [6].

Associations of crt-1 with chemical compounds

• The sequence shows a 61% identity with mouse calreticulin, increasing to 82% in the proline-rich region of the molecule [1].

Analytical, diagnostic and therapeutic context of crt-1

• Southern blotting of genomic DNA indicates that in C. elegans the calreticulin homologue exists in only one form as the product of a single gene [1].

References