Basic medical endocrinology - part 1 ppsx

[...]... Figure 16 Cyclic adenosine monophosphate (cyclic AMP) 30 Chapter 1 Introduction site of cleavage by Phospholipase C 2 3 O = - - - = - - 4 - O-P-O 1 O O O-P-O OH O Inositol Triphosphate 6 5 = - Diacylglycerol - OH OH - R 2 -C-O-C R 1 -C-O-C O C - O-P-O H2 O Figure 17 Phosphatidylinositol bisphosphate When cleaved by phospholipase C, inositol 1, 4,5triphosphate and diacylglycerol are formed R1 and R2... where a long polyadenine (polyA) tail is added 10 Chapter 1 Introduction O O - P=O 5' O 5 C H2 O Deoxyribose O 4 1 3 2 O O O - P=O CH3 HN O CH2 O O N O Thymine O NH2 O - P=O O N N CH2 N N O O Adenine O O O - P=O O N HN H2N N N CH2 O O Guanine O NH 2 O - P=O O N O N CH2 O O Cytosine O O - P=O 3' O Figure 3 Composition of DNA DNA is a polymer of the five-carbon sugar, deoxyribose, in diester linkage,... Introduction H1 H2 H1 response 2 binding domain response 2 H2 transducing domain response 1 response 1 Figure 11 Hormones 1 and 2 produce separate and distinct responses transduced by their unique receptors Chimeric receptors were produced by fusing the hormone binding domain of the receptor for hormone 1 to the signal transducing domain of the receptor for hormone 2 and vice versa Hormone 1 now elicits... membrane α γ β cytosol GDP G-protein subunits Figure 14 G-Protein-coupled receptor.The seven transmembrane α-helices are connected by three extracellular and three intracellular loops of varying length.The extracellular loops may be glycosylated, and the intracellular loops and C-terminal tail may be phosphorylated The receptor is coupled to a G-protein consisting of a GDP-binding alpha subunit closely... signals transmitted by hormones G-Protein-coupled receptors receive signals carried by a wide range of neurotransmitters, immune modulators, and paracrine factors More than 10 00 varieties of G-protein-coupled receptors may be expressed in humans, and about 30% of all effective pharmaceutical agents are said to target actions mediated by receptors in this superfamily.All G-protein-coupled receptors are composed... applied, but the maximal rate of secretion is not reached for at least 10 15 minutes In contrast, stored peptide and amine hormones may be released almost instantaneously 17 Hormones in Blood trans golgi 2 1 secretory vesicle secretory granule 3 4 plasma membrane Figure 9 Exocytosis Secretory vesicles (1) bud off the trans-Golgi compartment and (2) move into the cytosol, where they await a signal for... carbon 1 of each sugar The numbering system for the five carbons of deoxyribose is shown in blue at the top of the figure.The chemical bonds forming the backbone of the DNA chain are shown in blue The 5′ and 3′ ends refer to the carbons in deoxyribose 12 Chapter 1 Introduction transcription general factors and transcription cofactors complex Pll 1 introns 2 3 splicing mRNA 5 exons start pre-mRNA 4 1 2 1. .. found in small RNA molecules called transfer RNA (tRNA), each of which binds a particular amino acid and delivers it to the ribosome Alignment of amino acids in the proper sequence is achieved by the 13 Biosynthesis of Hormones primary RNA transcript 5' 1 2 3 4 5 3' alternatively spliced messenger RNAs 1 2 3 4 5 1 2 4 5 1 2 3 primary protein translation products N 2 3 4 5 C N C 2 4 5 N 2 3 C Figure... the loops and the carboxyl and amino-terminal tails vary in characteristic ways among the subgroups of these receptors Outward-facing components of the receptor, including parts of the α-helices, contribute to the hormone recognition and binding site.The cytosolic loops and carboxyl tail bind to specific G-proteins near the interface of the membrane and the cytosol G-Proteins are heterotrimers composed... in free solution at nanomolar (10 −9 M) or even picomolar (10 12 M) concentrations Steroid hormones and thyroid 18 Chapter 1 Introduction hormones, which have a limited solubility in water, circulate bound specifically to large carrier proteins synthesized in the liver Some protein and peptide hormones also circulate complexed with specific binding proteins (see Chapter 10 ) Bound hormones are in equilibrium . added. Biosynthesis of Hormones 9 10 Chapter 1. Introduction O CH 2 O - P=O O O CH 3 O HN N O Thymine O CH 2 O - P=O O O O O CH 2 O - P=O O O O O CH 2 O - P=O O O O O CH 2 O - P=O O O O O O N N N N NH 2 Adenine O HN N N N H 2 N Guanine N NH 2 O N Cytosine O.