Show simple item record

dc.contributor.advisor Tao, Yizhi Jane
dc.creatorJiang, Yunyun
dc.date.accessioned 2013-03-08T00:34:46Z
dc.date.available 2013-03-08T00:34:46Z
dc.date.issued 2012
dc.identifier.citation Jiang, Yunyun. "Structural and Functional Studies of the human cohesin subunits Rad21 and SA2." (2012) Diss., Rice University. https://hdl.handle.net/1911/70280.
dc.identifier.urihttps://hdl.handle.net/1911/70280
dc.description.abstract The cohesin complex is responsible for the fidelity of chromosomal segregation during mitosis. It consists of four core subunits namely Rad21/Mcd1/Sccl, Smc1, Smc3 and one of the yeast Scc3 orthologs SA1 or SA2. Sister chromatid cohesion is formed by the cohesin complex during DNA replication and maintained until the onset of anaphase. Among the many proposed models of how cohesin holds sister chromatids together, the 'core' cohesin subunits Smc1, Smc3 and Rad21/Mcd1/Scc1 are almost universally displayed as forming a contiguous ring. However, other than its supportive role in the cohesin ring, little is known about the fourth core protein SA1/SA2 - despite its physical association to the cohesin ring. To gain deeper insight into how physically and physiologically SA2 interacts with the cohesin complex, we performed structural characterization of SA2 and Rad21 and mapped the interaction region of the two proteins in vitro and ex vivo . We found SA2 interacts with Rad21 at multiple domains while Rad21 only interacts with SA2 through a 10 amino acid α-helical motif from 383-392aa. Deletion of these 10 amino acids or mutation of three conserved amino acids (L385, F389, and T390) in this α-helical motif prevents Rad21 from physically interacting with SA2/SA1 and causes premature sister chromatid separation in mitotic cells that often leads to aneuploidy. Our studies provide a model for how SA2 structurally strengthens the cohesin ring through its interaction with Rad21. Results from our structural characterization of these two proteins also provided directions for further investigation of the structural basis of protein-protein interaction in the cohesin complex.
dc.format.extent 150 p.
dc.format.mimetype application/pdf
dc.language.iso eng
dc.subjectHealth sciences
Environmental science
Pure sciences
Biological sciences
Cohesin
Rad21
SA2
Interactions
Aneuploidy
Mitosis
Cellular biology
Biochemistry
Oncology
dc.title Structural and Functional Studies of the human cohesin subunits Rad21 and SA2
dc.identifier.digital JiangY
dc.type.genre Thesis
dc.type.material Text
thesis.degree.department Biochemistry and Cell Biology
thesis.degree.discipline Natural Sciences
thesis.degree.grantor Rice University
thesis.degree.level Doctoral
thesis.degree.name Doctor of Philosophy


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record