MICHAEL AARON WEISS

..Protein evolution is constrained not only by structure and function but also by susceptibility to toxic misfolding...

..Dab(A8)-insulin illustrates the utility of non-standard amino acids in hypothesis-driven protein design...

..The cryptic threat of misfolding poses a universal constraint in the evolution of polypeptide sequences...

..Future development of clinical analogs lacking significant IGFR cross-binding may enhance the safety of insulin replacement therapy in patients with type 2 diabetes mellitus at increased risk of colorectal cancer...

..Structures of metastable disulfide isomers provide probes of the topography of an energy landscape...

..We speculate that the general danger of fibrillation has imposed a constraint in protein evolution, selecting for topologies unfavorable to amyloid formation...

..The intrinsic conformational propensities of a flexible disulfide-linked peptide thus define a folding nucleus, foreshadowing the structure of the native state...

..Zinc stapling provides a general strategy to modify the pharmacokinetic and biological properties of a subcutaneous protein depot...

..The structure of proinsulin provides a foundation for studies of insulin biosynthesis and its impairment in monogenic forms of diabetes mellitus...

..We propose that the Ile(A2) side-chain inserts within a chiral pocket of the receptor as part of insulin's hidden functional surface...

..Together, our studies define an "Achilles' heel" in a globular protein whose repair may enhance the stability of pharmaceutical formulations and broaden their therapeutic deployment in the developing world...

..Our studies demonstrate that photoscanning mutagenesis can decode the active conformation of a protein and so illuminate cryptic constraints underlying its evolution...

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..Implications for the hierarchical folding mechanisms of proinsulin and insulin-like growth factors are discussed...

..Optimizing the binding interaction of a nonconserved side chain on the surface of insulin may thus enhance its activity...

..In addition to their biophysical interest, ultrastable SCIs may enhance the safety and efficacy of insulin replacement therapy in the developing world...

..The Ala(A2) analog's low biological activity (0.5% relative to the parent monomer) highlights the importance of the A1-A8 alpha-helix in receptor recognition...

..Non-cooperative unfolding of the N-terminal A-chain alpha-helix resembles that observed in models of proinsulin folding intermediates and foreshadows the extensive alpha --> beta transition characteristic of mature fibrils...

..This seeming paradox suggests that insulin undergoes a change in conformation to expose Ile(A2) at the hormone-receptor interface...

..Exclusion of Leu among biological sequences suggests an evolutionary constraint on the dynamics of a Zn finger...

..By tethering the N- and C-terminal domains of the extracellular alpha subunit, insulin is proposed to stabilize an active conformation of the disulfide-linked transmembrane tyrosine kinase...

..Although lacking classical receptor-binding determinants, INS-6 binds to and activates the human insulin receptor. Its activity is greater than that of an analogous single-chain human insulin analog...

..Together, these considerations indicate that LFSE provides an important but incomplete description of the stringency and thermodynamic origin of metal-ion selectivity...

..The substantial receptor-binding activity of Arg(B5)-insulin (40% relative to wild type) demonstrates that the function of an insulin monomer can be uncoupled from its allosteric reorganization within zinc-stabilized hexamers...

..These mutations confer graded gene-regulatory activity in yeast within a physiological temperature range and so may provide novel probes for genetic analysis of a sex-specific transcriptional program in Drosophila development...

..Our results provide evidence that Val(A3), a site of mutation causing diabetes mellitus, contacts the insert domain-derived tail of the alpha-subunit in a hormone-receptor complex...

..Comparison of L- and D amino acid substitutions thus provides an example of the stereospecific control of an energy landscape by a helix-capping residue...

..Together, our results support a model in which the B-chain alpha-helix, functioning as an essential recognition element, docks against the L1 beta-helix of the insulin receptor...

..The possibility that the ubiquitination machinery participates in the regulation of sexual dimorphism is discussed...

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..In addition to its classic function to facilitate disulfide pairing, the connecting peptide may protect beta cells from toxic protein misfolding in the endoplasmic reticulum...

..C. Hodgkin. Future studies of the receptor-bound structure of insulin may enable design of novel agonists for the treatment of diabetes mellitus...

..Together, these results provide molecular links between the structure of the DM domain and its function in the regulation of sexual dimorphism...

..We speculate that the kinetic stability of a bent DNA complex is critical to the assembly and maintenance of a sex-specific transcriptional pre-initiation complex...

..This celebrated metaphor of Gould and Lewontin emphasizes the role of interlocking constraints in the evolution of biological structures...

..The inverse relationship between stereospecific stabilization and receptor binding strongly suggests that the B7-B10 beta-turn changes conformation on receptor binding...

..Enhanced flexibility of the native insulin monomer is in accord with molecular dynamics simulations. Such conformational fluctuations may initiate formation of an amyloidogenic nucleus and enable induced fit on receptor binding...

..The previously unsuspected role of M64 within a non-classical NLS may contribute to its invariance among SOX-related and LEF-1-related transcription factors...

..Native crystals belong to space group P2(1)2(1)2(1) and diffract to a resolution of 1.6 A with synchrotron radiation. Selenomethionine-containing crystals provide anomalous dispersion for phasing...

..We propose that male-specific gene regulation requires DNA bending above a critical threshold set by architectural requirements of enhanceosome assembly...

..We speculate that sites of intrinsic flexibility within a DNA control element provide hinges for its protein-directed reorganization in a transcriptional preinitiation complex...

..Our results demonstrate that this surface spans both chains of the insulin molecule and includes sites of rare human mutations that cause diabetes...

..Bass (Northwestern University). Aim 4 focuses on co-crystallization studies of the hormone-receptor complex with the Dodson laboratory. Each aim is supported by a solid foundation of preliminary results. ..

..We are studying sex-specific genes in fruit flies to gain insight into human birth defects, infertility syndromes, and cancers of the gonads. ..

..To demonstrate proof-of- principle, respective application of this enabling technology to the liver and pancreatic p cells of LIRKO and PIRKO mice is planned in collaboration with C. R. Kahn (Joslin Diabetes Center, Boston). ..

..Our results promise to have implications for the evolution of insulin-like sequences and the possible misfolding of human proinsulin in type II diabetes mellitus. ..

..Accordingly, our strategy may generalize to enhance the utility of diverse protein pharmaceuticals in the post-genomic era. ..

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..The objective of this application is to design an optimal insulin analog for safe and effective use in an implantable pump. ..

..Design principles will be validated through a series of functional assays and molecular studies to provide a solid scientific foundation for clinical translation. ..

..R. Kahn (Joslin Diabetes Center, Boston). ..

..To demonstrate proof-of- principle, respective application of this enabling technology to the liver and pancreatic p cells of LIRKO and PIRKO mice is planned in collaboration with C. R. Kahn (Joslin Diabetes Center, Boston). ..

..We are studying sex-specific genes in fruit flies to gain insight into human birth defects, infertility syndromes, and cancers of the gonads. ..

..The objective of this application is to design an optimal insulin analog for safe and effective use in an implantable pump. ..

..To demonstrate proof-of- principle, respective application of this enabling technology to the liver and pancreatic p cells of LIRKO and PIRKO mice is planned in collaboration with C. R. Kahn (Joslin Diabetes Center, Boston). ..

..Accordingly, our strategy may generalize to enhance the utility of diverse protein pharmaceuticals in the post-genomic era. ..

..This information is of basic importance in protein chemistry and likely to facilitate design of novel insulin for the treatment of diabetes mellitus. ..

..The systems under study are of broad biological interest with application to cancer biology and AIDS. ..

..The requested instruments will therefore significantly enhance the depth and scope of the major users' funded research and will provide general access to state-of-the-art calorimetric analysis to the University community...

..It will not only make an impact on research projects of Cleveland structural biology community but also create an active core of NMR structural biology experts trained in the most current and sophisticated techniques. ..

..Bass (Northwestern University). Aim 4 focuses on co-crystallization studies of the hormone-receptor complex with the Dodson laboratory. Each aim is supported by a solid foundation of preliminary results. ..

..This differential property is the basis on which Dr. Weiss proposes to identify factors responsible for on-pathway and off-pathway oxidative folding. ..

..The proposed pilot studies will dissect an insulin signaling pathway in a genetic model of senescence and aging (Aim 1) and a novel mechanism of metabolic homeostasis and insulin resistance in human obesity. ..