Lipid and Metabolism

OXPAT is the mammalian form of the PAT (perilipin, adipophilin, and TIP47) gene family that consists of proteins associated with lipid droplets (LDs) in fat-storing adipocyte cells.

The low density lipoprotein receptor coordinates the metabolism of cholesterol, an essential component of the mammalian cell plasma membranes. Study of this carefully balanced system has led to an enhanced understanding of cholesterol homeostasis at the cellular level. Receptor-mediated endocytosis (RME) is an important mechanism of metabolic regulation.

Caveolin-1 (CAV1) belongs to the caveolin family of integral membrane proteins 21-24 kD in size. This family of proteins forms the structural component of the caveolar membrane in caveolae, which are the specialized domains in plasma membrane that sequester lipids and proteins.

SREBP1 (sterol-regulatory-element-binding protein 2) is a basic-helix-loop-helix-leucine zipper (bHLH-ZIP) transcription factor. It regulates sterol and cholesterol homeostasis by controlling enzymes involved in cholesterol synthesis and uptake, e.g. HMG-CoA. The SREBP1 antibody was used in fundamental studies to dissect SREBP1 domains and downstream signaling (1).

The low density lipoprotein receptor coordinates the metabolism of cholesterol, an essential component of the mammalian cell plasma membranes. Study of this carefully balanced system has led to an enhanced understanding of cholesterol homeostasis at the cellular level. Receptor-mediated endocytosis (RME) is an important mechanism of metabolic regulation.

Carbohydrate response element binding protein (ChREBP) is a transcription factor involved in activating genes that encode enzymes of fatty acid biosynthesis in liver and adipose. It is believed to be a key controller of hepatic lipogenesis and has a partner MLX. One study used ChREBP antibodies to better understand the mechanisms of ChREBP transcription via promoter binding studies (1).

ABCG1 (ATP-binding cassette sub-family G member 1) is a transporter protein that is primarily involved in macrophage lipid homeostasis. It is a member of the superfamily of ATP-binding cassette (ABC) transporters and localizes to intracellular compartments associated with endoplasmic reticulum and golgi membranes.

Niemann-Pick type C (NPC) disease is a severe cell lipidosis characterized by the accumulation of unesterified cholesterol in the endosomal/lysosomal system. It is a lysosomal storage disorder that affects the viscera and the central nervous system which is caused by the accumulation of cholesterol in lysosomes (1). Niemann-Pick disease type C1 has a highly variable clinical phenotype and clinical features include variable hepatosplenomegaly and severe progressive neurological dysfunction such as ataxia, dystonia and dementia (2).

Mammalian target of rapamycin (mTOR) is a serine/threonine protein kinase and has been known to play its role in cell growth and proliferation. mTOR is activated by phosphorylationin response to growth factors, mitogens and hormones. Rapamycin is a macrolide antibiotic from Streptomyces hygroscopicus that specifically inhibit the activity of mTOR.

As the hormone ghrelin is linked to appetite and weight gain, as well as impaired glucose-induced insulin secretion, there is considerable interest in this peptide as a potential drug target. Although the overall lack of success in this field has been disappointing, research inhibiting the ghrelin-modifying enzyme GOAT (MBOAT4) has produced promising results.