The assembly of the quinary structure of involves the cooperative integrations of the noncovalent inter tetrameric interactions of multiple intermolecular contact sites, and there is a significant additive and/or synergistic effect between various sets of intermolecular contact sites. The earlier studies with human-nonhuman and nonhuman-nonhuman chimeric alpha-chains carrying a set of a sequence differences of the intermolecular contact have established the perturbation of such additive/synergistic interactions leads to the generation super-inhibitory alpha-chains. The set of linked- sequence differences of the contact sites present in pig alpha-chain and human-pig chimeric alpha-chain are enough to completely neutralize the Val-6(beta) dependent polymerization reaction. We hypothesize that we can identify these linked-contact site sequence differences and transplant these into human alpha-chain and endow with the polymerization neutralizing potential. We will increase the data base of polymerization inhibitory/neutralizing potential of linked-sequence differences of contact sites by assembling additional interspecies Beta-s hybrids (using alpha-chains of dog, cat and chicken, and the chimeric alpha-chains of these species) and identify multiple sets of linked sequence differences of the contact sites that are likely to neutralize the polymerization potential of the Beta-s-chains.These sequence differences will be grafted into human alpha-chain using modular construction approach that will involve chemical/enzymic ligation of four segments of alpha-globin with desired sequence differences as the primary approach, and site directed mutagenesis as the back up approach. If the transplanted sequences differences fail to endow the human alpha-chain the full polymerization inhibition and/or neutralization parent non-human or chimeric alpha-chain, these will be fine tuned by engineering additional contact site sequence differences. The linkage map of the interaction of contact sites the sequence differences of which neutralize the Beta-s polymerization potential, and functional complementation of these sequence differences from the cis and/or trans positions will be delineated by designing and assembling new alpha-chain constructs with subsets of the sequence differences.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Specialized Center--Cooperative Agreements (U54)
Project #
5U54HL070994-05
Application #
7406848
Study Section
Special Emphasis Panel (ZHL1)
Project Start
2007-04-01
Project End
2008-03-31
Budget Start
2007-04-01
Budget End
2008-03-31
Support Year
5
Fiscal Year
2007
Total Cost
$339,853
Indirect Cost
Name
Albert Einstein College of Medicine
Department
Type
DUNS #
110521739
City
Bronx
State
NY
Country
United States
Zip Code
10461
Chen, Qiuying; Fabry, Mary E; Rybicki, Anne C et al. (2012) A transgenic mouse model expressing exclusively human hemoglobin E: indications of a mild oxidative stress. Blood Cells Mol Dis 48:91-101
Finnegan, Eileen M; Turhan, Aslihan; Golan, David E et al. (2007) Adherent leukocytes capture sickle erythrocytes in an in vitro flow model of vaso-occlusion. Am J Hematol 82:266-75
Srinivasulu, Sonati; Acharya, A Seetharama; Prabhakaran, Muthuchidambaran et al. (2007) HbS-Savaria: the anti-polymerization effect of a single mutation in human alpha-chains. Protein J 26:523-32
Chen, Qiuying; Lalezari, Iraj; Nagel, Ronald L et al. (2005) Liganded hemoglobin structural perturbations by the allosteric effector L35. Biophys J 88:2057-67
Chen, Qiuying; Vekilov, Peter G; Nagel, Ronald L et al. (2004) Liquid-liquid phase separation in hemoglobins: distinct aggregation mechanisms of the beta6 mutants. Biophys J 86:1702-12
Chen, Qiuying; Bouhassira, Eric E; Besse, Arnaud et al. (2004) Generation of transgenic mice expressing human hemoglobin E. Blood Cells Mol Dis 33:303-7