Featured Pathways
Lymphocytes are one of the five kinds of white blood cells or leukocytes, circulating in the blood. Although mature lymphocytes all look pretty much alike, they are extraordinarily diverse in their functions. The most abundant lymphocytes are: B-Lymphocytes (often simply called B-Cells) and T-Lymphocytes (likewise called T-Cells) [Ref.1]. B-Cells are not only produced in the bone marrow but also[..]
The SM (Sphingomyelin) pathway is an evolutionarily conserved stress response system linking diverse environmental stresses (Ultraviolet, Heat Shock, Oxidative Stress, and Ionizing Radiation) to cellular effector pathways. Ceramide is the second messenger in this system and can be generated either by hydrolysis of SM through SM-specific PLC (Phospholipase-C) termed SMases (Sphingomyelinases) or[..]
The ability of multicellular organisms to maintain cellular homeostasis is critically dependent on a balance between cell survival and cell death (apoptosis). The responsiveness of individual cells to death signals varies greatly depending on the presence of continuous survival cues from the extracellular environment. The perturbation of normal cell survival mechanisms, leading to an increase in[..]
TGFB (Transforming growth factor-beta) is a multifunctional cytokine that regulates a wide variety of cellular functions, including cell growth, cellular differentiation, apoptosis, and wound healing. TGF-b signals are transmitted through two transmembrane serine/threonine kinase receptors TGFBR1 and TGFBR2 [Ref.1]. Initiation of the TGFB signaling cascade occurs upon ligand binding to TGFB[..]
Dynamic regulation of the actin cytoskeleton underpins a multitude of cellular processes, from cell movement and polarization1,2 to cell division.3 The actin cytoskeleton and the proteins involved in its regulation are also fundamentally linked to endocytosis and membrane trafficking.4,5 Members of the Rho family of small GTPases have emerged as important overseers of the actin cytoskeleton and a[..]
Our immune system is largely controlled by the action of pleiotropic cytokines and growth factors, small secreted proteins, which bind to receptors on the surface of immune cells to initiate an appropriate physiological response. The cellular response to cytokines and growth factors is predominantly executed by intracellular proteins known as the Janus kinases[..]
Calpain is an evolutionary old family of soluble, neutral, calcium-dependent proteases, which have the unique property of using protein cleavage to modify the activity/function of their substrate proteins. There are two major calpain isoforms in the brain, calpain-1 and calpain-2. Calpain-1 and Calpain-2 exhibit opposite functions in both synaptic plasticity and neurodegeneration. Calpain-1[..]
Members of the TNFR (Tumor Necrosis Factor Receptor) superfamily are important for cell growth and survival. CD27 is a member of the TNFR superfamily, which includes TNFR types I and II, NGFR (Nerve Growth Factor Receptor), CD30 (associated with Hodgkin lymphoma), Fas/Apo1 (CD95), CD40, 4–1BB, and OX40. These receptors are known to play a very important role in cell growth and differentiation,[..]
PKR (Protein Kinase-R) is a 68-kDa serine–threonine kinase that appears to play a primary role in mediating the antiviral activities of infected cells. PKR mediates apoptosis induced by many different stimuli, such as LPS (Lipopolysaccharides), TNF-Alpha (Tumour Necrosis Factor-Alpha), viral infection, or serum starvation. Viral infection leads to the increased expression and secretion of the[..]
The Eph family forms the largest group of RTKs (Receptor Tyrosine Kinases) comprising 14 members in mammals that play critical roles in diverse biological processes during development as well as in the mature animal. They are activated by membrane-bound ligands called Ephrins, which are classified into two subclasses based on their mode of membrane anchorage. The Ephrin-A ligands are GPI[..]
Ras is a membrane-associated guanine nucleotide-binding protein that is normally activated in response to the binding of extracellular signals, such as growth factors, RTKs (Receptor Tyrosine Kinases), TCR (T-Cell Receptors) and PMA (Phorbol-12 Myristate-13 Acetate). Ras signaling affects many cellular functions, which includes cell proliferation, apoptosis, migration, fate specification, and[..]
