Office: MH-501C
Phone: (657) 278-2056
Email:
nkeppetipola@
fullerton.edu
Lab: DBH-141
Phone: (657) 278-3682
Niroshika Keppetipola
Associate Professor BiochemistryResearch Interests
Determining the role of chemical modifications in RNA binding protein function
Key words: Post-Translational Modifications, Alternative Splicing, RNA binding proteins
Techniques: Biochemistry, Cell and Molecular Biology
An important way that cells respond to environment is by controlling gene expression and in turn protein expression. The splicing of mRNA intermediates is an important mechanism for cells to regulate protein expression and in turn control development and respond to changes in the environment. RNA binding proteins play an important role in controlling the process of splicing and in turn regulating the protein composition of the cell. Many of these RNA binding proteins occur as gene families with members sharing high primary and tertiary structure similarity but have distinct tissue-specific expression patterns. Moreover, members regulate over-lapping and distinct sets of target exons to elicit tissue-specific gene expression patterns. How highly structurally similar proteins can regulate distinct splicing outcomes is not well understood.
Recent studies highlight that many of these RNA binding proteins are modified by the addition of chemical groups such as acetate and phosphate. Thus, it is likely that these post-translational modifications play a role in RNA binding protein function and in turn in tissue-specific gene expression. Studies conducted in the lab aim to test this hypothesis.
Education
Post-doctoral – University of California, Los Angeles
PhD- Sloan Kettering Cancer Center, Cornell University
BSc. University of Colombo, Sri Lanka
Selected Publications
Anthony Truong, Michael Barton, Uyenphuong Tran, Montana Mellody, Devon Berger, Dean Madory, Elizabeth Hitch, Basma Jibrael, Nikolas Nikolaidis, Tyler Luchko, Niroshika Keppetipola. Unstructured linker regions play a role in the differential splicing activities of paralogous RNA binding proteins PTBP1 and PTBP2.
Journal of Biological Chemistry, Volume 300, Issue 3, 2024, 105733, ISSN 0021-9258.
Pina, J.M.; Hernandez, L.A.; Keppetipola, N.M. Polypyrimidine Tract Binding Proteins PTBP1 and PTBP2 Interact with Distinct Proteins Under Splicing Conditions
. PLoS One. (2022),17(2):e0263287. PubMed Central PMCID: PMC8812845.
Niroshika Keppetipola and Terri Patchen (2021) “Titrating Teaching: An Interdisciplinary Case Study of Online and Face-to-Face Undergraduate Biochemistry Instruction
” J Microbiol Biol Educ. doi: 10.1128/jmbe.v22i1.2603.
Camila Pimentel, Casin Le , Marisel R Tuttobene, Tomas Subils , Jasmine Martinez , Rodrigo Sieira ,Krisztina M Papp-Wallace, Niroshika Keppetipola, Robert A Bonomo, Luis A Actis , Marcelo E Tolmasky , Maria Soledad Ramirez (2021) “Human Pleural Fluid and Human Serum Albumin Modulate the Behavior of a Hypervirulent and Multidrug-Resistant (MDR) Acinetobacter baumannii Representative Strain
” Pathogens Apr 13;10(4):471
Ontiveros RJ, Hernandez L, Nguyen H, Hernandez Lopez AL, Shankar A, Kim E, Keppetipola N (2020) “Identification and Characterization of a Minimal Functional Splicing Regulatory Protein, PTBP1” Biochemistry 2020, 59 (50) 4766–4774
Post-Translational Modifications in Polypyrimidine Tract Binding Proteins PTBP1 and PTBP2. Pina JM#, Reynaga JM*, Truong AAM*, Keppetipola NM. Biochemistry. 2018 Jun 13. doi: 10.1021/acs.biochem.8b00256. [Epub ahead of print]
Multiple determinants of splicing repression activity in the polypyrimidine tract binding proteins, PTBP1 and PTBP2.Keppetipola NM, Yeom KH, Hernandez AL, Bui T*, Sharma S, Black DL. RNA . 2016 Aug;22(8):1172-80. doi: 10.1261/rna.057505.116. Epub 2016 Jun 10.
Keppetipola N, Sharma S, Li Q, and Black DL. (2012) “Neuronal regulation of Pre-mRNA Splicing by Polypyrimidine Tract Binding Proteins, PTBP1 and PTBP2” Crit Rev Biochem Mol Biol . 47(4):360-78. PMCID: PMC3422667
Keppetipola N, Jain R, Meineke B, Diver M, and Shuman S. (2009). “Structure-activity relationships in Kluyveromyces lactis gamma-toxin, a eukaryal tRNA anticodon nuclease.” RNA 15, 1036-44. PMCID: PMC2685522
Keppetipola N, and Shuman S. (2008). “A phosphate-binding histidine of binuclear metallophosphodiesterase enzymes is a determinant of 2', 3' cyclic nucleotide phosphodiesterase activity” J. Biol. Chem. 283, 30942-9. PMCID: PMC2576524
Keppetipola N, and Shuman S. (2007). “Characterization of the 2’, 3’ cyclic phosphodiesterase activities of Clostridium thermocellum polynucleotide kinase-phosphatase and bacteriophage lambda phosphatase” Nucleic Acids Res. 35, 7721-32. PMCID: PMC2190708
# CSUF graduate student * CSUF undergraduate student
Courses Taught
Spring 2024 Office Hours
Wed 12pm-1p, Fri 1pm-2pm in Zoom or by appointment.
