상세정보
Export to Refworks부가기능
Probing Transmembrane Domain Interactions with Short and Simple Artificial Proteins
상세 프로파일
| 자료유형 | 학위논문 |
|---|---|
| 서명/저자사항 | Probing Transmembrane Domain Interactions with Short and Simple Artificial Proteins. |
| 개인저자 | Federman, Ross Steven. |
| 단체저자명 | Yale University. Immunobiology. |
| 발행사항 | [S.l.]: Yale University., 2019. |
| 발행사항 | Ann Arbor: ProQuest Dissertations & Theses, 2019. |
| 형태사항 | 312 p. |
| 기본자료 저록 | Dissertations Abstracts International 81-03B. Dissertation Abstract International |
| ISBN | 9781085777483 |
| 학위논문주기 | Thesis (Ph.D.)--Yale University, 2019. |
| 일반주기 |
Source: Dissertations Abstracts International, Volume: 81-03, Section: B.
Advisor: DiMaio, Daniel. |
| 이용제한사항 | This item must not be sold to any third party vendors. |
| 요약 | Transmembrane proteins represent a large and important class of proteins that mediate crucial biological processes, including those fundamental to the immune response. The helical membrane-spanning domains of transmembrane proteins are typically comprised of amino acids with hydrophobic side-chains, and the precise sequence of amino acids in these protein segments is critical in determining their structure and function. Specific interactions between transmembrane domains aid in the proper folding, oligomerization, or complex formation of many proteins within membranes. However, a full understanding of how transmembrane sequences dictate their functional interactions remains elusive.High-resolution structural data of transmembrane domains is less abundant than of other proteins. Because of this, it has been relatively difficult to relate the amino acid sequences of transmembrane domains to their structures and ultimately their functional interactions. This inability to fully predict transmembrane protein interactions based on sequence identity has hampered efforts to fully understand how many cellular processes work and to engineer synthetic proteins as potential therapeutics. Decades of research has revealed some of the principles that underlie these interactions, but efforts have fallen short of providing a full explanation or "rule book" for transmembrane domain interactions.Here, we use genetic approaches with ultra-simple artificial transmembrane proteins in cultured cells to study these interactions. We show that short homo-polymeric polyLeucine transmembrane proteins with different amino acids substituted at single positions can activate the platelet-derived growth factor beta receptor or the erythropoietin receptor, resulting in cell transformation or proliferation. Testing ~100 different single amino acid substitutions at different positions in the central region of polyLeucine proteins yields surprising and complex patterns of activity, which were markedly affected by minor sequence changes within the more complex transmembrane domains of the target receptors. In addition, specific leucine residues distributed along the length of these proteins are required for activity, and the positions of the essential leucines differ based on the identity and position of the central substituted amino acid.This thesis highlights the complexity that exists in the rules underlying the principles of transmembrane domain action. We found that many, often subtle chemical changes in the transmembrane domains of these artificial proteins, or of the target receptors, resulted in fundamental differences in activity or specificity of these simple proteins.We found that similarly sized, but more chemically complex artificial transmembrane proteins, that activate the same receptors as these ultra-simple proteins, appear to work in a different fashion. We performed mutagenesis on target receptors and tuned the expression levels of these artificial proteins to gain a better understanding of their mechanisms. In general, different chemical complexities of these artificial proteins dictate different mechanisms of receptor activation, though in both cases, these mechanisms take place within the membrane. Furthermore, different mechanisms in receptor activation are implied even among these simpler polyLeucine proteins based only on the identity of the amino acid substitution at a single position.This thesis demonstrates that artificial proteins of minimal chemical complexity can be used as tools to systematically examine the rules that underlie transmembrane domain complex formation. Overall, Our results reveal that the rules governing specific interactions between transmembrane domains in living cells are complex, even within this greatly simplified system. |
| 일반주제명 | Immunology. Biochemistry. Genetics. |
| 언어 | 영어 |
| 바로가기 | 
: 이 자료의 원문은 한국교육학술정보원에서 제공합니다. |
