Target CRB3 Target background CRB3 (Crumbs homologue 3) is an apical transmembrane protein member of the CRB protein family reported to be associated with tight junctions at the apical surface of epithelial cells and to play a role in apical membrane morphogenesis and tight junction regulation. The formation and maintenance of tight junctions is essential for the development of epithelial cell polarity. Two CRB3 isoforms have been described and CRB3 is homologous to the Crumb protein found in Drosophila. CRB3 contains a putative signal peptide in its first 20 amino acids, a putative extracellular site, and a transmembrane domain. The intracellular domain contains a PDZ-binding motif which is involved in the interactions of CRB3 with PARD6A and MPP5. Loss of CRB3 expression in immortal baby mouse kidney (iBMK) cells was reported to render these cells tumorigenic, suggesting an important role for CRB3 function in maintaining epithelial junction formation and apicobasal polarity required for contact-inhibited growth, and to suppress invasion and metastasis. Target alias Crumbs homologue 3 Immunogen Full length protein Specificity The antibody recognizes the full length CRB3 protein but not the extra cellular domain of CRB3. Recognize the overexpressed human form and the endogenous form in mouse. Clone ID 14F9 Isotype IgG2c Preservative None Format Purified with protein G, stored in PBS pH 7.4 and lyophilized. Recommend starting dilution If reconstituted with deionized water in 100 µl: WB 1:1000, IHC 1:100, IF 1:100. Optimal dilution has to be determined by the user. Limitations Research Use Only Storage Lyophilized antibodies can be kept at 4ºC for up to 3 months and should be kept at -20ºC for long-term storage (2 years). To avoid freeze-thaw cycles, reconstituted antibodies should be aliquoted before freezing for long-term (1 year) storage (-80ºC) or kept at 4ºC for short-term usage (2 months). For maximum recovery of product, centrifuge the original vial prior to removing the cap. Further dilutions can be made with the assay buffer. After the maximum long-term storage period (2 years lyophilized or 1 year reconstituted) antibodies should be tested in your assay with a standard sample to verify if you have noticed any decrease in their efficacy. To limit antibody loss or degradation, BSA (final concentration 1%) and sodium azide (final concentration 0.02%) can be added to the suggested first dilution. It is important to first verify if those preservatives are compatible with your assay.