Natural Sciences Department Sapna Das Bradoo

Dr. Sapna Das-Bradoo, Ph.D. Microbiology
University of Delhi, India

Phone: 918-449-6503
Office: BA Science building 134 (BASC134)
Lab: BA Science building 133 (BASC133)
email: dasbrado@nsuok.edu

Research Interests

The broad objective of my research is to study proteins involved in DNA replication. DNA replication is an important step in the eukaryotic cell cycle, and accurate duplication of the genome is essential for cell viability. Failure to do so results in DNA breakage during replication and increased genome instability, which can cause cancer (Das-Bradoo and Bielinsky, 2010). It is crucial, therefore, to understand the entire process of DNA replication. My research will employ biochemical, molecular biology techniques, and genetics in the model organism, Saccharomyces cerevisiae. The roles of specific DNA replication proteins will be studied, which will help to gain a better understanding of their function.

Our main focus is on an essential DNA replication protein, known as minichromosome maintenance protein 10 (Mcm10). The evolutionary conserved Mcm10 has been implicated in both the initiation and elongation steps of DNA replication. S. cerevisiae Mcm10 is cell cycle regulated and interacts with the catalytic subunit of polymerase alpha, the only enzyme capable of starting DNA replication in vivo. Furthermore, I have shown that Mcm10 is di-ubiquitinated and in its di-ubiquitinated form Mcm10 releases polymerase alpha and interacts with proliferating cell nuclear antigen (PCNA) (Das-Bradoo et al., 2006). PCNA is the processivity factor for polymerase delta and polymerase epsilon, the polymerases that carry out the bulk DNA synthesis after polymerase alpha has started the process. Therefore, Mcm10 appears to be a key coordinator of the switch between polymerase alpha and polymerase delta/epsilon and is a putative target for anti-cancer therapy.

Students in my lab carry out experiments targeted to achieve a better understanding of Mcm10 and its functional significance.

Recent Publications

Das-Bradoo, S. & Bielinsky, A.-K. (2010). DNA replication and S phase checkpoint control. Nature Education (Invited review) 3(9): 50. Nature Education is an online resource for undergraduates launched by Nature Publishing Group (NPG). http://www.nature.com/scitable/topicpage/dna-replication-and-checkpoint-control-in-s-14202419

Das-Bradoo, S.*, Nguyen*, H.-D. & Bielinsky, A.-K. (2010). A PCNA damage code? PCNA ubiquitination in response to Okazaki fragment processing defects. Cell cycle 9: 3674-3679 (Invited peer-reviewed review) (*contributed equally). https://www.landesbioscience.com/journals/cc/Das-BradooCC9-18.pdf https://www.ncbi.nlm.nih.gov/pubmed/20930510

Das-Bradoo, S.*, Nguyen*, H.-D., Wood*, J.L., Ricke, R.M., Haworth, J.C. & Bielinsky, A.-K. (2010). Defects in DNA ligase I synthesis trigger PCNA ubiquitination at lysine 107. Nature Cell Biology 12: 74-79 (*contributed equally). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2799194/

Das-Bradoo, S. & A.-K. Bielinsky. (2009). Replication initiation point mapping: approach and implications. Methods Mol. Biol. 521: 105-120. (ed. J. Walker and J. Dalgaard), Humana Press Inc. https://pubmed.ncbi.nlm.nih.gov/19563103/

Das-Bradoo, S., Ricke, R.M. & Bielinsky, A.-K. (2006). Interaction between PCNA and di-ubiquitinated Mcm10 is essential for cell growth in budding yeast. Mol. Cell. Biol. 26: 4806-4817. https://journals.asm.org/doi/full/10.1128/MCB.02062-05

Current Students

Chance Hendrix Graduate student
Brandy Fultz Research Assistant
Lakelen Crain Undergraduate student
Dillon Cave Undergraduate student
Bobby Bezinque Undergraduate student
Noor Ahmed Undergraduate student
Miranda Beeman Undergraduate student
Stephen Cates Undergraduate student

Student Research Presentations

(March 2012 to date; Presenter indicated by asterisk *)

Hendrix, C.* and Sapna Das-Bradoo. Does Mcm10s function extend beyond DNA replication? 86th Annual AAAS SWARM meeting held at Tulsa, Oklahoma on March 31 April 4, 2012. (Poster presentation).

Schalo I.*, Logan Solberg and Sapna Das-Bradoo. Mcm10 coordinates DNA replication and checkpoint pathway. 86th Annual AAAS SWARM meeting held at Tulsa, Oklahoma on March 31 April 4, 2012. (Poster presentation). Ian Schalo was awarded second prize for his presentation.

Hendrix, C.* and Sapna Das-Bradoo. Does Mcm10s function extend beyond DNA replication? Undergraduate Research Day at Northeastern State University at Tahlequah, Oklahoma on April 25, 2012. (Poster presentation).

Schalo I.*, Logan Solberg and Sapna Das-Bradoo. Mcm10 coordinates DNA replication and checkpoint pathway. Undergraduate Research Day at Northeastern State University at Tahlequah, Oklahoma on April 25, 2012. (Poster presentation).

Schalo, I.*, Hendrix, C. and Sapna Das-Bradoo. Mcm10 and Mrc1 interact to coordinate DNA replication and the S-Phase checkpoint pathway. OK-INBRE Summer Undergraduate Research Conference, Oklahoma City on July 20, 2012. (Poster Presentation).

Hendrix, C.* and Sapna Das-Bradoo. Mcm10 and Mrc1 interaction is important for maintaining genome stability in Saccharomyces cerevisiae. Presented in the Biomedical section at Oklahoma Academy of Sciences held at University of Central Oklahoma, Edmond, Oklahoma on November 9, 2012. (Oral presentation).

Fultz, Brandy* and Sapna Das-Bradoo. Novel role of Mcm10 in leading strand DNA replication. Presented in the Biomedical section at Oklahoma Academy of Sciences held at University of Central Oklahoma, Edmond, Oklahoma on November 9, 2012. (Oral presentation).

Schalo, I.* and Sapna Das-Bradoo. Mcm10 and Mrc1 interact to coordinate DNA replication and S-phase checkpoint pathways. Presented in the Biomedical section at Oklahoma Academy of Sciences held at University of Central Oklahoma, Edmond, Oklahoma on November 9, 2012. (Poster presentation). I. Schalo was awarded the Best of Academy prize for his presentation.

Hendrix, C.* and Sapna Das-Bradoo. Using fluorescence microscopy to investigate the interaction between Mcm10 and Mrc1 in Saccharomyces cerevisiae. Oklahoma Research Day at Edmond, OK on March 8, 2013. (Oral presentation).

Fultz, B.*, Hendrix, C. and Sapna Das-Bradoo. A novel role of Mcm10 in leading strand DNA replication. Oklahoma Research Day at Edmond, OK on March 8, 2013. (Oral presentation).

Breedlove, D.*, Hendrix, C. and Sapna Das-Bradoo. Mapping interaction domains on Mcm10 and Mrc1 in budding yeast. Oklahoma Research Day at Edmond, OK on March 8, 2013. (Poster presentation).

Schalo, I.*, Hendrix, C. and Sapna Das-Bradoo. Decoding DNA replication and DNA damage pathways involved in cancer. Oklahoma EPSCOR 18th Annual Research day at the Capitol on April 11, 2013. (Poster presentation). I. Schalo was awarded the third prize for his presentation.

Darbandi, S.*, Fultz, Brandy and Sapna Das-Bradoo. A novel role of Mcm10 in leading strand DNA replication. Undergraduate Research Day at Northeastern State University at Tahlequah, Oklahoma on April 24, 2013. (Poster presentation). S. Darbandi was awarded the third prize for her presentation.

Schalo, I.*, Hendrix, C. and Sapna Das-Bradoo. Decoding DNA replication and DNA damage pathways involved in cancer. Undergraduate Research Day at Northeastern State University at Tahlequah, Oklahoma on April 24, 2013. (Poster presentation). I. Schalo was awarded the first prize for his presentation.

Breedlove, D.*, Hendrix, C. and Sapna Das-Bradoo. Understanding Mcm10 interaction with Mrc1 for potential cancer treatment. Undergraduate Research Day at Northeastern State University at Tahlequah, Oklahoma on April 24, 2013. (Poster presentation).

Cates, S.* and Sapna Das-Bradoo. Mcm10 interaction with Mrc1 is required for genomic stability in Saccharomyces cerevisiae. OK-INBRE Summer Undergraduate Research Conference, Oklahoma City on July 19, 2013.

Watts, J.* and Sapna Das-Bradoo. Efficient expression, purification and proteomic analysis of Mcm10 from Saccharomyces cerevisiae. OK-INBRE Summer Undergraduate Research Conference, Oklahoma City on July 19, 2013.

Cates, S.*, Crain, L. and Sapna Das-Bradoo. Mcm10 interaction with Mrc1 is required for maintaining genomic stability in Saccharomyces cerevisiae. Arkansas INBRE research conference at Fayetteville, Arkansas on October 18-19, 2013. (Poster presentation).

Fultz, B.* and Sapna Das-Bradoo. Coordination of DNA replication and checkpoint signaling via Mcm10 in budding yeast. Arkansas INBRE research conference at Fayetteville, Arkansas on October 18-19, 2013. (Poster presentation).

Hendrix, C.* and Sapna Das-Bradoo. Unraveling the role of Mcm10-Mrc1 interaction at the replication fork. Arkansas INBRE research conference at Fayetteville, Arkansas on October 18-19, 2013. (Poster presentation).