Author: Miss Muskan Sahu
Volume: 01
First Online: 2026
Pages: 141-199
DOI:

This chapter provides a comprehensive overview of transcription and RNA processing, highlighting their central roles in gene expression and regulation. It explains the process of transcription, including the functions of RNA polymerases (Pol I, Pol II, and Pol III), the stages of transcription initiation, elongation, and termination, and the regulatory roles of transcription factors, enhancers, and silencers in controlling gene activity. The chapter further describes posttranscriptional modifications such as 5′ capping, 3′ polyadenylation, and RNA splicing, which convert primary RNA transcripts into mature and functional RNA
molecules. It discusses the structure and function of introns, exons, the spliceosome, and alternative splicing in generating protein diversity. In addition, the chapter covers RNA editing, RNA interference mechanisms involving siRNA, miRNA, piRNA, and lncRNA, and the role of RNA–protein complexes in gene regulation. Overall, the chapter provides a detailed understanding of the molecular mechanisms that regulate transcription, RNA maturation, and gene expression, establishing a foundation for molecular biology, genetics, biotechnology, and biomedical research.