This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1hiq
From Proteopedia
PARADOXICAL STRUCTURE AND FUNCTION IN A MUTANT HUMAN INSULIN ASSOCIATED WITH DIABETES MELLITUS
Structural highlights
Disease[INS_HUMAN] Defects in INS are the cause of familial hyperproinsulinemia (FHPRI) [MIM:176730].[1] [2] [3] [4] Defects in INS are a cause of diabetes mellitus insulin-dependent type 2 (IDDM2) [MIM:125852]. IDDM2 is a multifactorial disorder of glucose homeostasis that is characterized by susceptibility to ketoacidosis in the absence of insulin therapy. Clinical fetaures are polydipsia, polyphagia and polyuria which result from hyperglycemia-induced osmotic diuresis and secondary thirst. These derangements result in long-term complications that affect the eyes, kidneys, nerves, and blood vessels.[5] Defects in INS are a cause of diabetes mellitus permanent neonatal (PNDM) [MIM:606176]. PNDM is a rare form of diabetes distinct from childhood-onset autoimmune diabetes mellitus type 1. It is characterized by insulin-requiring hyperglycemia that is diagnosed within the first months of life. Permanent neonatal diabetes requires lifelong therapy.[6] [7] Defects in INS are a cause of maturity-onset diabetes of the young type 10 (MODY10) [MIM:613370]. MODY10 is a form of diabetes that is characterized by an autosomal dominant mode of inheritance, onset in childhood or early adulthood (usually before 25 years of age), a primary defect in insulin secretion and frequent insulin-independence at the beginning of the disease.[8] [9] [10] Function[INS_HUMAN] Insulin decreases blood glucose concentration. It increases cell permeability to monosaccharides, amino acids and fatty acids. It accelerates glycolysis, the pentose phosphate cycle, and glycogen synthesis in liver. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe solution structure of a diabetes-associated mutant human insulin (insulin Los Angeles; PheB24-->Ser) was determined by 13C-edited NMR spectroscopy and distance-geometry/simulated annealing calculations. Among vertebrate insulins PheB24 is invariant, and in crystal structures the aromatic ring appears to anchor the putative receptor-binding surface through long-range packing interactions in the hydrophobic core. B24 substitutions are of particular interest in relation to the mechanism of receptor binding. In one analogue ([GlyB24]insulin), partial unfolding of the B chain has been observed with paradoxical retention of near-native bioactivity. The present study of [SerB24]insulin extends this observation: relative to [GlyB24]insulin, near-native structure is restored despite significant loss of function. To our knowledge, our results provide the first structural study of a diabetes-associated mutant insulin and support the hypothesis that insulin undergoes a change in conformation on receptor binding. Paradoxical structure and function in a mutant human insulin associated with diabetes mellitus.,Hua QX, Shoelson SE, Inouye K, Weiss MA Proc Natl Acad Sci U S A. 1993 Jan 15;90(2):582-6. PMID:8421693[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||
Categories: Human | Large Structures | Hua, Q X | Inouye, K | Shoelson, S E | Weiss, M A | Hormone

