CIDEC

This gene encodes a member of the cell death-inducing DNA fragmentation factor-like effector family. Members of this family play important roles in apoptosis. The encoded protein promotes lipid droplet formation in adipocytes and may mediate adipocyte apoptosis. This gene is regulated by insulin and its expression is positively correlated with insulin sensitivity. Mutations in this gene may contribute to insulin resistant diabetes. A pseudogene of this gene is located on the short arm of chromosome 3. Alternatively spliced transcript variants that encode different isoforms have been observed for this gene. [provided by RefSeq, Dec 2010]

Full Name

Cell Death Inducing DFFA Like Effector C

Function

Binds to lipid droplets and regulates their enlargement, thereby restricting lipolysis and favoring storage. At focal contact sites between lipid droplets, promotes directional net neutral lipid transfer from the smaller to larger lipid droplets. The transfer direction may be driven by the internal pressure difference between the contacting lipid droplet pair. Its role in neutral lipid transfer and lipid droplet enlargement is activated by the interaction with PLIN1. May act as a CEBPB coactivator in the white adipose tissue to control the expression of a subset of CEBPB downstream target genes, including SOCS1, SOCS3, TGFB1, TGFBR1, ID2 and XDH. When overexpressed in preadipocytes, induces apoptosis or increases cell susceptibility to apoptosis induced by serum deprivation or TGFB treatment. As mature adipocytes, that express high CIDEC levels, are quite resistant to apoptotic stimuli, the physiological significance of its role in apoptosis is unclear. May play a role in the modulation of the response to osmotic stress by preventing NFAT5 to translocate into the nucleus and activate its target genes expression.

Biological Process

Apoptotic process Source: MGI
Execution phase of apoptosis Source: UniProtKB
Lipid droplet organization Source: UniProtKB
Regulation of apoptotic process Source: GO_Central

Cellular Location

Endoplasmic reticulum; Nucleus; Lipid droplet. Diffuses quickly on lipid droplet surface, but becomes trapped and clustered at lipid droplet contact sites, thereby enabling its rapid enrichment at lipid droplet contact sites.

Involvement in disease

In omental adipose tissue of obese patients matched for BMI, expression levels tend to correlate with insulin sensitivity. Expression is increased 2-3 fold in the group of patients with high insulin sensitivity, compared to the insulin-resistant group. This observation is consistent with the idea that triglyceride storage in adipocytes plays an important role in sequestering triglycerides and fatty acids away from the circulation and peripheral tissues, thus enhancing insulin sensitivity in liver and muscle. This effect is not significant in subcutaneous adipose tissue (PubMed:18509062). In subcutaneous adipose tissue of diabetic patients, tends to negatively correlate with body mass index and total fat mass, independently of insulin sensitivity (PubMed:18334488).
Lipodystrophy, familial partial, 5 (FPLD5):
A form of lipodystrophy characterized by loss of subcutaneous adipose tissue affecting limb, femorogluteal and subcutaneous abdominal fat, preservation of visceral, neck and axilliary fat, hepatomegaly, hepatic steatosis and insulin-resistant diabetes.

PTM

Ubiquitinated and targeted to proteasomal degradation, resulting in a short half-life. Protein stability depends on triaclyglycerol synthesis, fatty acid availability and lipid droplet formation (By similarity).