Molecular Biology 101

This course offers a comprehensive introduction to the central dogma of molecular biology, guiding you through the flow of genetic information from DNA to proteins. Beginning with the discovery of DNA as the genetic material and progressing through the molecular mechanisms of replication, transcription, and translation, you will gain a strong foundation in the principles that underpin modern genetics and biotechnology.

Through clear explanations, historical perspectives, and visual examples, you will explore:

• The four key properties of genetic material: replication, storage, expression, and variation.

• Pioneering experiments by Griffith, Avery–MacLeod–McCarty, Hershey–Chase, and others that established DNA as the hereditary molecule.

• DNA structure and stability: nucleotides, Chargaff’s rules, the Watson–Crick double helix, alternative DNA forms, and the forces that stabilize them.

• DNA replication: semiconservative replication, alternative models, replication origins and forks, DNA polymerases and their proofreading roles, Okazaki fragments, leading and lagging strands, and replication in both prokaryotes and eukaryotes, including the role of telomeres and telomerase.

• The genetic code: triplet codons, degeneracy, start/stop signals, universality, and experimental evidence from Crick, Nirenberg, Matthaei, and others.

• Transcription: RNA polymerase function, promoters and sigma factors in bacteria, transcription initiation and termination, eukaryotic transcription (RNA polymerases I, II, and III), general transcription factors, cis- and trans-acting elements, chromatin remodeling, and RNA processing (5′ cap, poly-A tail, and splicing).

• RNA splicing: ribozymes, spliceosomes, snRNAs, snRNPs, and the biological roles of introns in alternative splicing, exon shuffling, microRNAs, and gene regulation.

• Translation: ribosome structure and function, tRNA charging, initiation (Shine–Dalgarno in bacteria, Kozak sequence in eukaryotes), elongation, termination, polysomes, and unique mechanisms in eukaryotic translation.

• Protein structure and function: the four structural levels of proteins, how polypeptides fold, and the relationship between protein structure, diversity, and biological function.

• Medical insights: classic examples such as alkaptonuria, PKU, and sickle-cell anemia, illustrating how mutations in DNA alter proteins and phenotypes.

By the end of this course, you will be able to:

• Explain the chemical and physical basis of DNA structure and replication.

• Describe the classic experiments that revealed how genetic information is stored and copied.

• Understand how DNA is transcribed into RNA and translated into proteins.

• Connect the molecular processes of replication, transcription, and translation to genetic variation, protein function, and human disease.

• Build the essential foundation for advanced study in molecular biology, genetics, and biotechnology.