Joel F. Habener – författare

Diabetes mellitus is rapidly increasing in prevalence throughout both developed and developing countries. The social and economic burden of this disease is estimated to cost 14 billion dollars worldwide. In the USA alone, 15 million individuals are diabetic, nearly half of them unaware of their condition. Complications of diabetes mellitus are the leading causes for blindness, limb amputation and chronic renal failure and kidney transplantation in industrialized countries. Further, diabetes mellitus per se and the metabolic derangement associated with diabetes are important risk factors for cardiovascular disease. Diabetes, as defined by an elevated fasting blood glucose level is presently subdivided in etiologically distinct groups. The most prevalent being type 2 (adult onset) diabetes characterized by insulin resistance and failure of the ~-cell to supply insulin in amounts sufficient to meet the body's needs. Type 1 (juvenile) diabetes, most commonly with an onset during childhood and adolescence, is caused by an auto-immune destruction of the pancreatic ~-cells. The causations of both type 1 and type 2 diabetes involve a combination of complex genetic traits and environmental influences. A third category are the mature onset diabetes of the young (MODY). This comparatively small group of patients (-10% of diabetes) presents relative early in life «30 years of age) compared to the more common late onset type 2 diabetes.

The peptide hormones are small proteins that regulate cellular metabolism through their specific interactions with tissues of the endocrine, nervous, and immune systems, as well as in embry­ onic development. During the past ten years, refinements in the techniques of recombinant DNA technology have resulted in the cloning of genes encoding approximately 50 different hormonal and regulatory peptides, including those in which the peptides themselves and the mRNAs encoding the peptides are present in only trace amounts in the tissues of origin. In addition to provid­ ing the coding sequences of recognized hormonal and regulatory peptides, gene sequencing has uncovered new bioactive peptides encoded in the precursor pro hormones that are then liberated along with the hormonal peptides during cellular cleavages of the precursors. The encoding of multiple peptides in a single mono­ cistronic mRNA appears to be a genetic mechanism for the gener­ ation of biologic diversification without requiring amplification of gene sequences. Two of the objectives in the assembly of this book are to pre­ sent, in one volume, the known primary structures of the genes encoding several of the polypeptide hormones and related regulatory peptides, and to provide an account of the various ap­ proaches that have been used to identify and select the cloned genes encoding these polypeptides. The contents of the two in­ troductory chapters are intended to provide the reader with a brief background of the approaches to gene cloning and the struc­ ture and expression of hormone-encoding genes.

The peptide hormones are small proteins that regulate cellular metabolism through their specific interactions with tissues of the endocrine, nervous, and immune systems, as well as in embry­ onic development. During the past ten years, refinements in the techniques of recombinant DNA technology have resulted in the cloning of genes encoding approximately 50 different hormonal and regulatory peptides, including those in which the peptides themselves and the mRNAs encoding the peptides are present in only trace amounts in the tissues of origin. In addition to provid­ ing the coding sequences of recognized hormonal and regulatory peptides, gene sequencing has uncovered new bioactive peptides encoded in the precursor pro hormones that are then liberated along with the hormonal peptides during cellular cleavages of the precursors. The encoding of multiple peptides in a single mono­ cistronic mRNA appears to be a genetic mechanism for the gener­ ation of biologic diversification without requiring amplification of gene sequences. Two of the objectives in the assembly of this book are to pre­ sent, in one volume, the known primary structures of the genes encoding several of the polypeptide hormones and related regulatory peptides, and to provide an account of the various ap­ proaches that have been used to identify and select the cloned genes encoding these polypeptides. The contents of the two in­ troductory chapters are intended to provide the reader with a brief background of the approaches to gene cloning and the struc­ ture and expression of hormone-encoding genes.

The peptide hormones are small proteins that regulate cellular metabolism through their specific interactions with tissues of the endocrine, nervous, and immune systems, as well as in embry­ onic development. During the past ten years, refinements in the techniques of recombinant DNA technology have resulted in the cloning of genes encoding approximately 50 different hormonal and regulatory peptides, including those in which the peptides themselves and the mRNAs encoding the peptides are present in only trace amounts in the tissues of origin. In addition to provid­ ing the coding sequences of recognized hormonal and regulatory peptides, gene sequencing has uncovered new bioactive peptides encoded in the precursor pro hormones that are then liberated along with the hormonal peptides during cellular cleavages of the precursors. The encoding of multiple peptides in a single mono­ cistronic mRNA appears to be a genetic mechanism for the gener­ ation of biologic diversification without requiring amplification of gene sequences. Two of the objectives in the assembly of this book are to pre­ sent, in one volume, the known primary structures of the genes encoding several of the polypeptide hormones and related regulatory peptides, and to provide an account of the various ap­ proaches that have been used to identify and select the cloned genes encoding these polypeptides. The contents of the two in­ troductory chapters are intended to provide the reader with a brief background of the approaches to gene cloning and the struc­ ture and expression of hormone-encoding genes.

Diabetes mellitus is rapidly increasing in prevalence throughout both developed and developing countries. The social and economic burden of this disease is estimated to cost 14 billion dollars worldwide. In the USA alone, 15 million individuals are diabetic, nearly half of them unaware of their condition. Complications of diabetes mellitus are the leading causes for blindness, limb amputation and chronic renal failure and kidney transplantation in industrialized countries. Further, diabetes mellitus per se and the metabolic derangement associated with diabetes are important risk factors for cardiovascular disease. Diabetes, as defined by an elevated fasting blood glucose level is presently subdivided in etiologically distinct groups. The most prevalent being type 2 (adult onset) diabetes characterized by insulin resistance and failure of the ~-cell to supply insulin in amounts sufficient to meet the body's needs. Type 1 (juvenile) diabetes, most commonly with an onset during childhood and adolescence, is caused by an auto-immune destruction of the pancreatic ~-cells. The causations of both type 1 and type 2 diabetes involve a combination of complex genetic traits and environmental influences. A third category are the mature onset diabetes of the young (MODY). This comparatively small group of patients (-10% of diabetes) presents relative early in life «30 years of age) compared to the more common late onset type 2 diabetes.