Biomaterial Database

Carbonic anhydrase III in obese Zucker rats. 1993

C J Lynch, and W A Brennan, and T C Vary, and N Carter, and S J Dodgson

Department of Cellular and Molecular Physiology, College of Medicine, Pennsylvania State University, Hershey 17033.

Proteins from 5- to 7-wk-old lean and obese Zucker rats were separated by one-dimensional sodium dodecyl sulfate (SDS) and two-dimensional SDS-isoelectric focusing-polyacrylamide gel electrophoresis. Laser densitometry revealed an obesity-related decrease in the concentration of a 28-kDa cytosolic adipocyte protein, the most abundant protein in adipocytes from lean Zucker rats. Microsequencing revealed the identity of this protein to be carbonic anhydrase III (CA III). The identity and obesity-related decrease was further confirmed using isoform-specific antisera and CA III enzyme activity measurements made by 18O mass spectrometry. Immunoblotting studies also revealed that CA III is present in at least two charge isoforms in adipocytes. Our data indicate that lean Zucker rat adipocytes may represent the richest source of CA III in nature (24% of the cytosolic protein content). An obesity-related decrease in both the concentration and activity of CA III was observed in two lipogenic tissues, liver and white fat, but not in soleus muscle. Adipocyte CA III activity was no longer depressed when hyperinsulinemic obese rats were made insulin deficient by streptozotocin injection. This suggests that the obesity-related decrease in CA III may be related to the hyperinsulinemia as well as to the insulin hyperresponsiveness that adipocytes from obese Zucker rats of this age display.

UI	MeSH Term	Description	Entries
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D008297	Male		Males
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D008970	Molecular Weight	The sum of the weight of all the atoms in a molecule.	Molecular Weights,Weight, Molecular,Weights, Molecular
D009765	Obesity	A status with BODY WEIGHT that is grossly above the recommended standards, usually due to accumulation of excess FATS in the body. The standards may vary with age, sex, genetic or cultural background. In the BODY MASS INDEX, a BMI greater than 30.0 kg/m2 is considered obese, and a BMI greater than 40.0 kg/m2 is considered morbidly obese (MORBID OBESITY).
D011924	Rats, Zucker	Two populations of Zucker rats have been cited in research--the "fatty" or obese and the lean. The "fatty" rat (Rattus norvegicus) appeared as a spontaneous mutant. The obese condition appears to be due to a single recessive gene.	Zucker Rat,Zucker Rats,Rat, Zucker
D002256	Carbonic Anhydrases	A family of zinc-containing enzymes that catalyze the reversible hydration of carbon dioxide. They play an important role in the transport of CARBON DIOXIDE from the tissues to the LUNG. EC 4.2.1.1.	Carbonate Dehydratase,Carbonic Anhydrase,Anhydrases, Carbonic,Dehydratase, Carbonate
D003920	Diabetes Mellitus	A heterogeneous group of disorders characterized by HYPERGLYCEMIA and GLUCOSE INTOLERANCE.
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D000273	Adipose Tissue	Specialized connective tissue composed of fat cells (ADIPOCYTES). It is the site of stored FATS, usually in the form of TRIGLYCERIDES. In mammals, there are two types of adipose tissue, the WHITE FAT and the BROWN FAT. Their relative distributions vary in different species with most adipose tissue being white.	Fatty Tissue,Body Fat,Fat Pad,Fat Pads,Pad, Fat,Pads, Fat,Tissue, Adipose,Tissue, Fatty