P. N. Rangarajan, born in Bengaluru in the south Indian state of Karnataka, secured a PhD from the Indian Institute of Science (IISc) in 1989 and did his post doctoral work at Salk Institute for Biological Studies during 1990-92.^[2] After serving Howard Hughes Medical Institute as a research associate for a year, he returned to India to join IISc at the department of biochemistry in 1993 where he is a professor. At IISc, he has been carrying out research on how neurotropic viruses induce changes in eukaryotic gene expression in humans.^[3] He leads a team of scientists engaged in the studies of Pichia pastoris, a methylotrophic yeast species, with regard to its transcription factors and the regulation of carbon metabolism.^[4] He has also done extensive work on vaccine development against infectious diseases such as rabies, hepatitis B and Japanese encephalitis and he and his colleagues were successful in developing a new DNA-based vaccine against rabies.^[5] Later, they improved the vaccine performance by combining the DNA-based rabies vaccine with a controlled quantity of inactivated virus prepared through cell culture.^[6] The work earned Rangarajan and his colleagues Patent Cooperation Treaty^[7] and Indian patents^[8] and the vaccine, reportedly cheaper to produce than conventional cell culture rabies vaccines, is being marketed by Indian Immunologicals Limited, under the brand name, Dinarab.^[9] His studies have been documented by way of a number of articles^{[10][note 2]} of which many have been listed by online article repositories such as Google Scholar^[11] and ResearchGate.^[12]

Rangarajan's work has attracted research by other scientists^[13] and he has delivered invited speeches or keynote addresses including the lecture on Gene Regulation in Eukaryotes: Diversity in general Transcription factors at IIT Madras^[14] and the address on Transcriptional interference in the methylotrophic yeast, Pichia pastoris at Indian Institute of Science Education and Research, Thiruvananthapuram in October 2012.^[15] He was the co-convenor of the lecture workshop on Recent Advances in Biotechnology of Health and Disease (BHD-2011) organized by Madurai Kamaraj University in 2011^[16] and has been involved in conducting open courses on Eukaryotic Gene Expression.^[17]

Rangarajan is married to Radha and the couple has two children, Karthik and Meghana. The family lives in Rajajinagar in Bengaluru.^[18]

Rangarajan received the National Bioscience Award for Career Development of the Department of Biotechnology in 2001.^[19] The National Academy of Sciences, India elected him as a fellow in 2002.^[20] The Council of Scientific and Industrial Research awarded him Shanti Swarup Bhatnagar Prize, one of the highest Indian science awards in 2007.^[21] The Indian Academy of Sciences elected him as a fellow the same year^[22] and he became an elected fellow of the Indian National Science Academy in 2017.^{[23][note 3]}

• Saha, Sougata; Ramanathan, Anand; Rangarajan, Pundi N. (2006). "Regulation of Ca2+/calmodulin kinase II inhibitor α (CaMKIINα) in virus-infected mouse brain". Biochemical and Biophysical Research Communications. 350 (2): 444–449. doi:10.1016/j.bbrc.2006.09.066. PMID 17010311.
• Nagendrakumar, S. B.; Madhanmohan, M.; Rangarajan, P. N.; Srinivasan, V. A. (2009). "Genetic analysis of foot-and-mouth disease virus serotype A of Indian origin and detection of positive selection and recombination in leader protease- and capsid-coding regions". Journal of Biosciences. 34 (1): 85–101. doi:10.1007/s12038-009-0011-9. PMC 7090849. PMID 19430121.
• Nagaraj, Viswanathan Arun; Prasad, Dasari; Rangarajan, Pundi N.; Padmanaban, Govindarajan (2009). "Mitochondrial localization of functional ferrochelatase from Plasmodium falciparum". Molecular and Biochemical Parasitology. 168 (1): 109–112. doi:10.1016/j.molbiopara.2009.05.008. PMID 19523497.
• Nagaraj, Viswanathan Arun; Prasad, Dasari; Arumugam, Rajavel; Rangarajan, Pundi N.; Padmanaban, Govindarajan (2010). "Characterization of coproporphyrinogen III oxidase in Plasmodium falciparum cytosol". Parasitology International. 59 (2): 121–127. doi:10.1016/j.parint.2009.12.001. PMID 20006984.
• Vijay Kumar, N.; Rangarajan, P. N. (2011). "Catabolite repression of phosphoenolpyruvate carboxykinase by a zinc finger protein under biotin- and pyruvate carboxylase-deficient conditions in Pichia pastoris". Microbiology. 157 (12): 3361–3369. doi:10.1099/mic.0.053488-0. PMID 21948049.

• "Shanti Swarup Bhatnagar Prize for 2007 given away". Hindustan Times. 20 December 2008.
• "Pundi Narasimhan Rangarajan". List of articles. Loop. 2017.