Hypoxia-inducible factor 1 (HIF-1) allows cells to respond to changing levels of oxygen in the environment. HIF-1 is a heterodimeric transcription factor consisting of alpha and beta subunits. Under normal conditions HIF-1 alpha is continuously synthesized and degraded. HIF-1 alpha degradation is mediated through an oxygen-dependent degradation domain that is hydroxylated and leads to ubiquitylation and proteolysis. HIF-1 beta on the other hand is constitutively expressed and localizes to the nucleus.
The CD11 protein is actually a heterodimer complex that consists of CD11b and CD18. CD11 is involved in numerous adhesion-related associations between cells such as monocytes, macrophages, natural killer (NK) cells, and granulocytes. CD11 also regulates the uptake of complement-coated particles within cells. It has also gained usage as a microglial marker for tissues derived from the nervous system.
The extracellular matrix (ECM) is the external framework found between individual cells that comprise higher order structures like tissues and organs. The ECM composition of vertebrates is dominated by a class of molecules known as collagens - each with unique features suited for a particular function and location. Collagen proteins are made up of three subunit polypeptides that vary in length. Through a unique repeated (Gly-X-Y) sequence, these components associate to form a structurally regular triple helix.
The protein CD11b has been implicated in the various adhesion-related interactions of cells such as monocytes, macrophages, natural killer (NK) cells, and granulocytes. It is part of a heterodimer that consists of CD11b and CD18. It also modulates the uptake of complement-coated particles within the cell. It is commonly used as a microglial marker in tissues derived from the nervous system.
