Disease relevance of SNTB2

• Immunomicroscopy and co-immunoprecipitations from insulinoma INS-1 cells confirmed the occurrence of ICA512-beta2-syntrophin complexes in vivo [1].
• Two major clinical patterns emerged: patients with deficiency of beta2-syntrophin and alpha-dystrobrevin presented with severe congenital weakness and died in the first year of life, and two patients with deficiency of alpha-dystrobrevin had congenital muscular dystrophy with complete external ophthalmoplegia [2].

High impact information on SNTB2

• Dephosphorylation of beta2-syntrophin and Ca2+/mu-calpain-mediated cleavage of ICA512 upon stimulation of insulin secretion [3].
• Binding of its cytoplasmic tail to beta2-syntrophin suggests that ICA512 connects secretory granules to the utrophin complex and the actin cytoskeleton [3].
• A comparison of our human cDNA sequence with the GenBank expressed sequence tag (EST) data base has identified a relative from human skeletal muscle, EST25263, which is probably a human homologue of the published mouse syntrophin 2 [4].
• We have mapped the human basic component of A1 and EST25263 genes to chromosomes 8q23-24 and 16, respectively [4].
• Furthermore, we demonstrate for the first time that components of the dystrophin-associated protein complex, including alpha1-, beta1-, and beta2-syntrophin, dystrophin, and dystrobrevin, interact with Kir2 channels, as demonstrated by immunoaffinity purification and affinity chromatography from skeletal and cardiac muscle and brain [5].

Anatomical context of SNTB2

• Unlike mice, beta2-syntrophin is expressed at the sarcolemma in post-natal human skeletal muscle [2].
• Finally, we show that INS-1 cells, like muscle cells, contain beta2-syntrophin-utrophin oligomers [1].

Associations of SNTB2 with chemical compounds

• In vitro binding of the beta2-syntrophin PDZ domain to ICA512 required both ICA512's C-terminal region and an internal polypeptide preceding its tyrosine phosphatase-like domain [1].
• Luminescent silica nanotubes SNT-2 (loaded with coumarion laser dye 2) and SNT-3 (loaded with anthracene laser dye 3) were prepared by sol-gel cocondensation of functional dyes and TEOS in a cholesterol-based organogel system [6].

Physical interactions of SNTB2

• The carboxyterminus of the ATP-binding cassette transporter A1 interacts with a beta2-syntrophin/utrophin complex [7].

References