Integrins make a choice ignaling researchers have only a few factors with which to explain a whole lot of biology. On page 407, Goel et al. describe how two integrin variants channel the actions of a single factor, insulin-like growth factor (IGF), into two distinct pathways that induce either adhesion or proliferation. The ␤ 1A integrin variant was known to be associated with proliferation and...

A successful immune response depends on the capacity of immune cells to travel from one location in the body to another--these cells are rapid migrators, travelling at speeds of microm/minute. Their ability to penetrate into tissues and to make contacts with other cells depends chiefly on the beta2 integrin known as LFA-1. For this reason, we describe the control of its activity in some detail....

T he article by Striz et al in this issue of Chest (see page 882) examines @32 integrin and ICAM-1 ex pression on human alveolar macrophages in patients with sarcoidosis and in control subjects. To put this interesting article in context, a brief overview of the background leading to this work is necessary. The cell population recovered by bronchoalveolar lavage (BAL) from normal lungs is predo...

We investigated roles of alpha4 integrins during hematopoiesis using mutant and chimeric mice. Yolk sac erythropoiesis and migration of hematopoietic progenitors to fetal liver, spleen, and bone marrow can occur without alpha4 integrins. Although terminal differentiation of these progenitors is possible without alpha4 integrins, these receptors are essential to maintain normal hematopoiesis in ...

Integrin receptors mediate cell-cell and cell-extracellular matrix (ECM) interactions in many different cell types, including neuronal cells. Earlier studies have shown a clear role for integrins in axon extension and cell adhesion/migration in CNS inflammation. Here we summarize more recent work that shows integrin functions in many phases of neural development, from neuroblast migration to sy...

Physiological as well as pathological blood vessel formation are fundamentally dependent on cell-matrix interaction. Integrins, a family of major cell adhesion receptors, play a pivotal role in development, maintenance, and remodeling of the vasculature. Cell migration, invasion, and remodeling of the extracellular matrix (ECM) are integrin-regulated processes, and the expression of certain int...

Cadherins and integrins are intrinsically linked through the actin cytoskeleton and share common signaling molecules. Although mechanosensing by the integrin-actin axis has long been appreciated, a growing body of literature now demonstrates that cadherins also transduce and respond to mechanical forces. Mounting evidence shows that mechanically driven crosstalk between integrins and cadherins ...

Leukocyte adhesion is of pivotal functional importance. The adhesion involves several different adhesion molecules, the most important of which are the leukocyte beta 2-integrins (CD11/CD18), the intercellular adhesion molecules, and the selectins. We and others have extensively studied the specificity and binding sites in the integrins and the intercellular adhesion molecules for their recepto...

Adhesion receptors play diverse roles during animal development and require precise spatiotemporal regulation, which is achieved through the activity of their binding partners. Integrins, adhesion receptors that mediate cell attachment to the extracellular matrix (ECM), connect to the intracellular environment through the cytoplasmic adapter protein talin. Talin has two essential functions: orc...

Clathrin-associated endocytic adapters recruit cargoes to coated pits as a first step in endocytosis. We developed an unbiased quantitative proteomics approach to identify and quantify glycoprotein cargoes for an endocytic adapter, Dab2. Surface levels of integrins beta1, alpha1, alpha2, and alpha3 but not alpha5 or alphav chains were specifically increased on Dab2-deficient HeLa cells. Dab2 co...