Application Methods: Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting
Background: BNIP3 (Bcl-2/E1B-19kDa interacting protein 3) is a pro-apoptotic mitochondrial protein and Bcl-2 family member that contains a Bcl-2 homology 3 (BH3) domain and a carboxyl-terminal transmembrane (TM) domain (1-3). While BNIP3 has a predicted molecular weight of about 22 kDa, it runs anomalously on SDS-PAGE and includes a band of around 60 kDa that may be a dimeric form that is not reduced (2). BNIP3 associates with anti-apoptotic family members Bcl-2, Bcl-xL, and the adenovirus homologue E1B-19kDa. BNIP3 is distinct from other Bcl-2 family members that contain only the BH3 domain in that the TM domain, and not the BH3 domain, is required for mitochondrial targeting and pro-apoptotic activity (4). In addition to apoptosis, BNIP3 has been implicated in necrosis (5) and autophagy (6-11). In hypoxic conditions, BNIP3 can induce mitochondrial autophagy (mitophagy) by disrupting the Bcl-2-Beclin-1 complex (9). BNIP3 can also promote mitophagy by triggering the translocation of the E3 ubiquitin ligase Parkin to the mitochondria (10) or by directly binding LC3 on the autophagosome (11). BNIP3 may also localize to the endoplasmic reticulum (ER) where it can selectively induce the autophagic clearance of ER (ERphagy) (11). Increased expression of BNIP3 under hypoxic conditions is mainly regulated by the transcription factor HIF-1α (12-14). Silencing of the BNIP3 promoter by methylation has been observed in several types of cancer cells and may play an important role in their survival (14-18).
Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting
Background: Lysosome-associated membrane protein 1 and 2 (LAMP1 and LAMP2) are two abundant lysosomal membrane proteins (1,2). Both are transmembrane proteins and are heavily glycosylated at the amino-terminal luminal side of the lysosomal inner leaflet, which protects the proteins from proteolysis (3). The carboxy terminus of LAMP1 is exposed to the cytoplasm and contains a tyrosine sorting motif that targets LAMP to lysosomal membranes (4). LAMP1 and LAMP2 are 37% homologous in their protein sequences. Both LAMP1 and LAMP2 are involved in regulating lysosomal motility during lysosome-phagosome fusion and cholesterol trafficking (5,6).
Application Methods: Immunohistochemistry (Paraffin)
Background: p27 Kip1 is a member of the Cip/Kip family of cyclin-dependent kinase inhibitors. Like its relatives, p57 Kip2 and p21 Waf1/Cip1, the ability to enforce the G1 restriction point is derived from its inhibitory binding to CDK2/cyclin E and other CDK/cyclin complexes. Expression levels of p27 are upregulated in quiescent cells and in cells treated with cAMP or other negative cell cycle regulators. Downregulation of p27 can be induced by treatment with interleukin-2 or other mitogens; this involves phosphorylation of p27 and its degradation by the ubiquitin-proteasome pathway (1-4).