Apr 2009
IRIG: Adiponectin and Shp2 in PNAS
04/27/2009 11:00
Adiponectin is an
adipokine whose activity is determined by
protein multimerization. There are 3 adiponectin complexes in
circulation: trimer, hexamer, and high‑molecular‑weight forms (HMW) of
18‑36 monomers. The 3 forms of adiponectin display distinct biochemical
characteristics and exert nonoverlapping biological functions. In
obesity, adiponectin expression and the molecule multimerization are
both reduced. These changes may contribute to lipid disorder and insulin
resistance. It is not clear what gene regulates the multimerization of
adiponectin. In a recent study, a gene by the name of disulfide‑bond A
oxidoreductase (DsbA) has been found to control the multimer formation.
Please see the paper and commentary at this link:
http://www.ncbi.nlm.nih.gov/pubmed/19011089?dopt=Citation
The activities of many signaling proteins are regulated by kinase
(phosphorylation) and phosphatase (dephosphorylation). A balance of the
two types of enzymes/modifications is required for precise control of
intracellular signal transduction. This is observed in the control of
insulin secretion. In a recent study, Shp2, a widely expressed protein
tyrosine phosphatase (PTP), has been found to regulate insulin secretion
in Beta‑cells. Shp2 controls signaling by receptors for growth factors,
cytokines, and hormones. Shp2 binds to tyrosine‑phosphorylated IRS
proteins and operates in insulin responsive tissue cells. B‑cell
specific knockout of Shp2 led to deficiency in insulin production.
Please see the paper at this link:
http://www.ncbi.nlm.nih.gov/pubmed/19380737?dopt=Citation
By Jianping at PBRC/LSU
‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑
Jianping Ye, MD
Professor of Molecular Biology
Pennington Biomedical Research Center
Louisiana State University System
6400 Perkins Road
Baton Rouge, LA 70808
Phone: (225)763‑3163
E‑mail: yej@pbrc.edu
Webpage: http://labs.pbrc.edu/generegulation/index.htm
protein multimerization. There are 3 adiponectin complexes in
circulation: trimer, hexamer, and high‑molecular‑weight forms (HMW) of
18‑36 monomers. The 3 forms of adiponectin display distinct biochemical
characteristics and exert nonoverlapping biological functions. In
obesity, adiponectin expression and the molecule multimerization are
both reduced. These changes may contribute to lipid disorder and insulin
resistance. It is not clear what gene regulates the multimerization of
adiponectin. In a recent study, a gene by the name of disulfide‑bond A
oxidoreductase (DsbA) has been found to control the multimer formation.
Please see the paper and commentary at this link:
http://www.ncbi.nlm.nih.gov/pubmed/19011089?dopt=Citation
The activities of many signaling proteins are regulated by kinase
(phosphorylation) and phosphatase (dephosphorylation). A balance of the
two types of enzymes/modifications is required for precise control of
intracellular signal transduction. This is observed in the control of
insulin secretion. In a recent study, Shp2, a widely expressed protein
tyrosine phosphatase (PTP), has been found to regulate insulin secretion
in Beta‑cells. Shp2 controls signaling by receptors for growth factors,
cytokines, and hormones. Shp2 binds to tyrosine‑phosphorylated IRS
proteins and operates in insulin responsive tissue cells. B‑cell
specific knockout of Shp2 led to deficiency in insulin production.
Please see the paper at this link:
http://www.ncbi.nlm.nih.gov/pubmed/19380737?dopt=Citation
By Jianping at PBRC/LSU
‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑
Jianping Ye, MD
Professor of Molecular Biology
Pennington Biomedical Research Center
Louisiana State University System
6400 Perkins Road
Baton Rouge, LA 70808
Phone: (225)763‑3163
E‑mail: yej@pbrc.edu
Webpage: http://labs.pbrc.edu/generegulation/index.htm
|
IRIG: Brown fat in Human
04/20/2009 11:18
Brown fat is known to
produce heat for maintenance of the body
temperature in rodents. Brown adipocytes have a high density of
mitochondria thus make it "brown" in color. Mitochondria in brown
adipocytes are unique in that it oxidizes fatty acid and glucose to
generate heat, not ATP. This feature is due to expression of uncoupling
protein 1 (UCP‑1) that prevents ATP production in the mitochondria. It
has been controversial about existence and function of brown fat in
human. Now, this issue is resolved by three papers in the New England
Journal of Medicine. In these studies, it was found that human body does
have brown fat, but not every body have it. It is found in 7.5% of Women
and 3.5% of man. It produces heat in response to cold environment in
healthy man. It's mass is reduced in obese condition. See attached PDF
files of the three papers and a mini review. These papers are
recommended by Dr. Eugene Chen at the University of Michigan.
Brown fat minireview
Brown fat in healthy adults
Brown fat in healthy men
Brown fat in men and women
Regards,
By Jianping at PBRC/LSU
‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑
Jianping Ye, MD
Professor of Molecular Biology
Pennington Biomedical Research Center
Louisiana State University System
6400 Perkins Road
Baton Rouge, LA 70808
Phone: (225)763‑3163
E‑mail: yej@pbrc.edu
Webpage: http://labs.pbrc.edu/generegulation/index.htm
temperature in rodents. Brown adipocytes have a high density of
mitochondria thus make it "brown" in color. Mitochondria in brown
adipocytes are unique in that it oxidizes fatty acid and glucose to
generate heat, not ATP. This feature is due to expression of uncoupling
protein 1 (UCP‑1) that prevents ATP production in the mitochondria. It
has been controversial about existence and function of brown fat in
human. Now, this issue is resolved by three papers in the New England
Journal of Medicine. In these studies, it was found that human body does
have brown fat, but not every body have it. It is found in 7.5% of Women
and 3.5% of man. It produces heat in response to cold environment in
healthy man. It's mass is reduced in obese condition. See attached PDF
files of the three papers and a mini review. These papers are
recommended by Dr. Eugene Chen at the University of Michigan.
Brown fat minireview
Brown fat in healthy adults
Brown fat in healthy men
Brown fat in men and women
Regards,
By Jianping at PBRC/LSU
‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑
Jianping Ye, MD
Professor of Molecular Biology
Pennington Biomedical Research Center
Louisiana State University System
6400 Perkins Road
Baton Rouge, LA 70808
Phone: (225)763‑3163
E‑mail: yej@pbrc.edu
Webpage: http://labs.pbrc.edu/generegulation/index.htm