Molecular biology and structural biology are both critical fields at the forefront of current scientific advancements, studying life at both the molecular and atomic levels.
Molecular biology focuses on the interactions and functions of biomolecules, while structural biology provides insight into the physical components that underpin these interactions. Together, they advance our understanding of biological processes, paving the way for innovations in healthcare, biotechnology, and genetic research.1
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Core Concepts of Molecular Biology
At the heart of molecular biology are three fundamental molecules: DNA, RNA, and proteins. DNA (deoxyribonucleic acid) is the hereditary material that carries genetic information, comprising sequences of nucleotides that encode genes.2
RNA (ribonucleic acid) serves as the intermediary in gene expression, transcribing the genetic information that comes from DNA and translating it into proteins. Proteins are essential for nearly every biological function: acting as enzymes, structural components, and signaling molecules.3
Processes of Gene Expression
Gene expression involves two key processes: transcription and translation. During transcription, an enzyme called RNA polymerase binds to a gene's promoter region, unwinding the DNA and synthesizing a complementary RNA strand.4
This newly formed RNA strand serves as a template for the subsequent translation process. At this stage, the RNA is translated into a protein at the ribosome, where transfer RNA (tRNA) delivers the corresponding amino acids, facilitating the assembly of a protein chain.5
Gene Regulation and Key Techniques
Gene regulation ensures that genes are expressed at the right times and in the right cells. Techniques such as Polymerase Chain Reaction (PCR), CRISPR-Cas9 gene editing, and recombinant DNA technology have revolutionized molecular biology, enabling the precise manipulation of genetic material.6
Learn more about Genetics
Your Body's Molecular Machines
Core Concepts of Structural Biology
Structural biology aims to understand the physical shapes of biomolecules and how these shapes relate to their functions. By studying molecular structures, researchers can gain insight into the mechanisms of action of proteins, nucleic acids, and other biomolecules.7
Essential Molecules
Proteins function as key biomolecules in structural biology: comprised of amino acid chains that fold into specific shapes, ultimately determining their function and activity. Nucleic acids, which facilitate genetic information storage and transmission, play a crucial role in heredity and protein synthesis.8
Enzymes, specialized proteins that catalyze biochemical reactions, are also essential for metabolic processes - understanding their structures is crucial for developing inhibitors and drugs that can effectively adjust their activity.
This information facilitates the design of targeted medications that can combat various diseases by precisely interfering with enzyme function.9
Structural Biology Techniques
Several techniques are fundamental to structural biology, such as X-ray crystallography, which provides high-resolution images of crystallized proteins.10
Nuclear Magnetic Resonance (NMR) spectroscopy allows for the observation of molecular dynamics in solution, while cryo-electron microscopy (cryo-EM) offers insights into biomolecules without the need for crystallization.11, 12
Find out more about Nuclear Magnetic Resonance
Penn Structural Biology: The Future of Drug Discovery
Applications and Importance
Drug Discovery
Molecular and structural biology play pivotal roles in drug discovery. Understanding the molecular structures of target proteins allows researchers to design small molecules that specifically interact with these targets.13
For example, structural insights into protein kinase B (AKT) have brought about the development of targeted cancer therapies.14
Genetics and Disease Research
Structural biology aids in deciphering genetic mutations linked to various diseases. By analyzing the structures of mutated proteins, researchers can identify how these mutations can affect function and sometimes contribute to disease.
Insights gained from these structural analyses can guide the design of new targeted therapies and personalized medicine, giving improved therapeutic results and minimizing side effects for individual patients. These advancements prove the importance of structural biology in modern biomedical research and therapeutic development.15
Biotechnology
In biotechnology, molecular and structural biology are used to create genetically engineered organisms for a variety of fields, such as agriculture, biofuels, and pharmaceuticals. These advancements enable more efficient crop yields, sustainable energy sources, and effective medicines.
An example of this is the production of insulin using recombinant DNA technology, which has transformed modern diabetes treatments. Utilizing biotechnology has not only improved patient outcomes but has also allowed for large-scale production, reducing costs and increasing accessibility to this essential medication.16
Discover more on Drug Discovery
Recent Advances and Future Directions
Current developments in structural and molecular biology, such as the integration of artificial intelligence (A.I.) and machine learning into modeling complex biomolecular structures, are at the forefront of major scientific advancements.
These kinds of technologies promise to accelerate drug discovery and deepen our understanding of biological systems.17 Single-cell genomics advancements allow researchers to analyze gene expression at the single-cell level, providing insights into cellular heterogeneity.18
Molecular and structural biology are vital fields that continue to drive innovations across various scientific disciplines.
Progress in these areas has facilitated substantial developments in medicine, biotechnology, and environmental science. As researchers further develop our understanding of these subjects, there is the potential for valuable discoveries that could address future challenges.
References
1. Alberts, B., et al. (2014). Molecular Biology of the Cell. Garland Science. Available from: https://www.ncbi.nlm.nih.gov/books/NBK21054/.
2. Watson, J.D., & Crick, F.H.C. (1953). Molecular structure of nucleic acids: a structure for deoxyribose nucleic acid. Nature, 171(4356), 737-738. DOI: 10.1038/171737a0.
3. Berg, J.M., Tymoczko, J.L., & Stryer, L. (2012). Biochemistry. W.H. Freeman. ISBN: 1429229365, 9781429229364.
4. Glick, B.R., & Pasternak, J.J. (2010). Molecular Biotechnology: Principles and Applications of Recombinant DNA. ASM Press. ISBN: 1555816126, 9781555816124.
5. Noller, H.F. (2012). RNA structure and ribosome function. Nature Reviews Microbiology, 10(4), 230-239. DOI: 10.1042/bj2290001.
6. Doudna, J.A., & Charpentier, E. (2014). The new frontier of genome engineering with CRISPR-Cas9. Science, 346(6213), 1258096. DOI: 10.1126/science.1258096.
7. Branden, C., & Tooze, J. (2012). Introduction to Protein Structure. Garland Science. DOI: 10.1201/9781136969898.
8. Alberts, B. (2015). Molecular Biology of the Cell. Garland Science. DOI: 10.1201/9781315735368.
9. Voet, D., & Voet, J.G. (2011). Biochemistry. John Wiley & Sons. ISBN: 0470917458, 9780470917459
10. Rupp, B. (2010). Biomolecular Crystallography: Principles, Practice, and Application to Structural Biology. Elsevier. DOI: 10.1201/9780429258756.
11. Wüthrich, K. (2002). NMR of proteins and nucleic acids. Biospectroscopy, 1(1), 1-12. ISBN: 978-0-471-82893-8.
12. Bai, X.C., et al. (2015). How cryo-EM is revolutionizing structural biology. Nature Reviews Molecular Cell Biology, 16(9), 607-617. DOI: 10.1016/j.tibs.2014.10.005.
13. Hajduk, P.J., & Greer, J. (2007). A decade of fragment-based drug design: strategies, successes, and challenges. Nature Reviews Drug Discovery, 6(3), 211-219. DOI: 10.1038/nrd2220.
14. Manning, B.D., & Toker, A. (2017). AKT/PKB signaling: Navigating the network. Cell, 169(3), 381-405. DOI: 10.1016/j.cell.2017.04.001.
15. Peng, Y., Alexov, E., & Basu, S. (2019) Structural Perspective on Revealing and Altering Molecular Functions of Genetic Variants Linked with Diseases. International Journal of Molecular Sciences, 20(3), 548. DOI: 0.3390/ijms20030548.
16. Pandurangan, A.P., et al. (2017) Genomes, structural biology and drug discovery: combating the impacts of mutations in genetic disease and antibiotic resistance. Biochemical Society Transactions, 45(2), 303-311. DOI: 10.1042/BST20160422.
17. Senior, A.W., et al. (2020). Improved protein structure prediction using potentials from deep learning. Nature, 577(7792), 706-710. DOI: 10.1038/s41586-019-1923-7.
18. Zhao, T., et al. (2018). Single-Cell RNA-Seq Reveals Dynamic Early Embryonic-like Programs during Chemical Reprogramming, 23(1), 31-45. DOI: 10.1016/j.stem.2018.05.025.
Further Reading