High impact information on CRT1

• LPAT2 was colocalized with calreticulin in the ER by immunofluorescence microscopy and subcellular fractionation [1].
• Aberrant localization of the ER chaperones calreticulin and binding protein (BiP) and the endogenous seed storage protein cruciferin in the periplasmic space suggests that overproduction of recombinant scFv-Fc disturbs normal ER retention and protein-sorting mechanisms in the secretory pathway [2].
• The folding of glycoproteins in the endoplasmic reticulum (ER) depends on a quality control mechanism mediated by the calnexin/calreticulin cycle [3].
• Reglucosylation is catalyzed by the ER lumenal located enzyme UDP-glucose glycoprotein glucosyltransferase, but as UDP-glucose is synthesized in the cytosol, a UDP-glucose transporter is required in the calnexin/calreticulin cycle [3].
• Phylogenetic studies and expression analysis show that higher plants contain two distinct groups of CRTs: a CRT1/CRT2 group and a CRT3 group [4].

Biological context of CRT1

• Furthermore, analysis of posttranslational modifications revealed differences in the glycosylation status among members within the CRT1/CRT2 isoform group [4].
• The presence of two distinct CRT isoform groups, with distinct expression patterns and posttranslational modifications, supports functional specificity among plant CRTs and could account for the multiple functional roles assigned to CRTs [4].
• The partial cDNA showed sequence homology to the calcium-binding region common to calreticulin and calnexin [5].

Anatomical context of CRT1

• Calreticulin (CRT) is a calcium-binding protein in the endoplasmic reticulum (ER) with an established role as a molecular chaper-one [6].
• Calreticulin (CRT) is a multifunctional protein mainly localized to the endoplasmic reticulum in eukaryotic cells [4].
• Furthermore, after treatment with the Ca(2+) ionophore ionomycin, ER microsomes from NT1 cells overproducing CRT showed a 2-fold increase in the amount of (45)Ca(2+) released, and a 2- to 3-fold increase in the amount of (45)Ca(2+) retained compared with wild type [7].
• Calreticulin and the chemical stain 3,3'-dihexyloxacarbocyanine iodide also provided useful markers when monitoring PDs in cell wall preparations by light microscopy [8].

Analytical, diagnostic and therapeutic context of CRT1

• Using light and electron microscopy and immunostaining for callose and calreticulin, we showed that suspension cells laid down abundant PDs in division walls, and that vestiges of these structures were retained as half PDs even when the cell-to-cell contacts were disrupted during culture growth [8].

References