Novel insulin from the bullfrog: its structure and function in protein secretion by hepatocytes

Thesis/Dissertation · Thu Jan 01 04:00:00 EST 1987

OSTI ID:6281097

Hulsebus, J J

Bullfrog insulin was extracted and purified from the pancreas of Rana catesbeiana adults using gel filtration and reverse phase high performance liquid chromatography. Amino acid analysis of bullfrog insulin revealed 52 amino acids instead of the most common number of 51. The most unique features of bullfrog insulin is a two amino acid extension on the amino terminus (A1) of the A chain. This is the only insulin to date that has an extension at this position. Bullfrog and porcine insulin increase protein secretion from bullfrog adult and three developmental stages of tadpole hepatocytes in a totally defined, serum-free culture system. The hormone slightly stimulates protein secretion by premetamorphic and early prometamorphic tadpoles. Late prometamorphic tadpoles respond to bullfrog and porcine insulin with higher concentrations of secreted protein than either of the two previous developmental stages. Insulin treated adult hepatocytes secrete significantly higher concentrations of protein than any of the tadpole stages. /sup 35/S-methionine and /sup 35/S-cysteine were added to the culture medium for twelve hours. Proteins secreted into the medium were separated using SDS polyacrylamide linear gradient gels. Densitometer scans of autoradiograms did not show an increases in any specific proteins, but did show a generalized increase in all secreted proteins for both adults, and tadpoles.

• Research Organization: Iowa State Univ. of Science and Technology, Ames (USA)
• OSTI ID: 6281097
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AGE DEPENDENCE
AMINO ACIDS
AMPHIBIANS
ANIMAL CELLS
ANIMALS
AQUATIC ORGANISMS
AUTORADIOGRAPHY
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMISTRY
BIOLOGICAL FUNCTIONS
CARBOXYLIC ACIDS
CHEMICAL COMPOSITION
CHEMISTRY
CHROMATOGRAPHY
CYSTEINE
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTROPHORESIS
EVEN-ODD NUCLEI
FROGS
FUNCTIONS
HORMONES
INSULIN
ISOTOPES
LIGHT NUCLEI
LIPOTROPIC FACTORS
LIQUID COLUMN CHROMATOGRAPHY
LIVER CELLS
METHIONINE
MOLECULAR STRUCTURE
NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PEPTIDE HORMONES
PROTEINS
RADIOISOTOPES
SECRETION
SEPARATION PROCESSES
SOMATIC CELLS
SULFUR 35
SULFUR ISOTOPES
THIOLS
VERTEBRATES