Recombinant Mouse Integrin alpha 6 beta 4 Protein, CF

Recombinant Mouse Integrin alpha 6 beta 4 Protein, CF Summary

Product Specifications

Product Datasheets

Carrier Free

CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our recombinant proteins. Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant protein to be stored at a more dilute concentration. The carrier free version does not contain BSA.

In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or as an ELISA standard. In contrast, the carrier free protein is recommended for applications, in which the presence of BSA could interfere.

Background: Integrin alpha 6 beta 4

Integrin alpha 6 beta 4 is primarily an epithelial and Schwann cell laminin-binding integrin. While the alpha 6 subunit can also pair with beta 1, beta 4 pairs only with alpha 6 (1, 2). Expression of the non-covalent heterodimer composed of ~150 kDa alpha 6/CD49f and 150-200 kDa beta 4/CD104 type I transmembrane glycoprotein subunits is required for hemidesmosome formation (1, 3). The alpha 6 subunit contains an I (inhibitory) domain and a cleavage site that creates extracellular domain (ECD) heavy and transmembrane light chains. Mouse and human ubiquitously express the X1 isoform, while alternate splicing in the human ECD also creates X2 and X1X2 isoforms. Cytoplasmic splicing creates A and B isoforms in both mouse and human (4, 5). The beta 4 subunit cytoplasmic domain is unusually long (~1000 aa) and contains four type III fibronectin repeats that bind intracellular hemidesmosomal components (1-4). beta 4 alternative splicing between repeats 2 and 3 creates isoform 2 (deletion of 65 aa) and 3 (deletion plus insertion of 52 aa), which differ in tissue distribution (2, 5). The 876 aa mouse alpha 6 heavy chain shares 98% aa sequence identity with rat and 92-93% with human (X1), bovine, and canine  alpha 6. The 684 aa mouse beta 4 ECD shares 96% aa sequence identity with rat and 87‑92% with human, bovine, and equine  beta 4. Mutation of alpha 6 beta 4 can cause EB-PA, or epidermolysis bullosa (detachment of epidermis from basement membrane) with pyloric atresia, that is neonatally lethal in humans if severe (1, 3, 5). On Schwann cells, alpha 6 beta 4 cooperates with dystroglycan to stabilize the myelin sheath, and mediates attachment to the basal lamina (6, 7). alpha 6 beta 4 is also expressed on vessel‑associated muscle progenitors and on lung vascular endothelial cells, where it binds HLA class I molecules and enhances antigen presentation and cell proliferation (8‑10). High alpha 6 beta 4 expression correlates with invasiveness of carcinomas (1). In carcinomas, it binds IGF-I and the tetraspanin CD151, which promotes phosphorylation of beta 4 by EGF R, disrupting hemidesmosomes and allowing tumor cell migration (1, 11‑14). alpha 6 beta 4 signaling can also amplify tumor production of VEGF, ErbB and SPARC proteins (1, 15‑17).

Related Research Areas

• Actin Stress Fibers and Focal Adhesions During EMT
• Adhesion Molecules
• Adhesion Molecules in Angiogenesis
• Adhesion Molecules on VSMC
• Adhesive Interactions in Allergy and Asthma
• Embryonic and Induced Pluripotent Stem Cell Markers
• Epithelial Cell Polarity
• Integrins and Associated Molecules