Definition of Molecular Biology

Among the many molecules present in living beings, it is worth highlighting the lipids, carbohydrates, genes and proteins. However, most scientists focus their research in genes and proteins, since the former contain the information required to synthesize proteins, which present a wide diversity of functions within cells.

central dogma of molecular biology

The central dogma of molecular biology is a concept first enunciated more than 50 years ago by Francis Crick that defines the relationships between macromolecules: DNA, RNA, and proteins. Is a

hypothesis initial that describes the process in which DNA encodes genes in a linear way through RNA, which is a kind of template for protein synthesis.

The first phase is transcription, which is the synthesis of RNA using an enzyme that uses DNA as a template to produce the RNA polymer. The next phase is translation, which consists of protein synthesis from the protein molecule. RNA, this happens in the ribosomes and the molecule that contains this information is the messenger RNA (mRNA). Initially, polypeptides are synthesized which must be coupled with each other to form proteins and fulfill their function within the cell. For this to happen, the DNA has to replicate, which ensures the multiplication of the cells.

Differences between molecular biology, biochemistry and genetics

There is a relationship between molecular biology, biochemistry and genetics. The three branches provide us with detailed information on how the organisms at the molecular level, although they focus on different areas and applications.

The study of biochemistry is more focused on nucleic acids, lipids, enzymes, carbohydrates, and the chemical effects that occur when large amounts of a substance are encountered, such as the effects of poisons. This area uses research-based methods of organic chemistry

The study of genetics focuses on hereditary traits and how changes in the genetic code affect an organism. The concept of heritability means that genetics is often studied at the population level, making it a much larger-scale field than molecular biology.

Study methods in molecular biology

Throughout history, as humanity we have faced infectious diseases, for which it has become necessary to optimize diagnoses, and that they be also specific, sensitive and fast, for which various techniques and research methods have emerged in order to prevent, control and treat diseases. diseases.

The most used techniques in this branch are cloning molecular, the use of the polymerase enzyme, the chain reaction, electrophoresis, blotting, among others. With these techniques, molecular biologists are able to extract, isolate and quantify the molecules of interest, although there are also digital and bioinformatic methods that allow the modeling of these.

Undoubtedly, the polymerase chain reaction (PCR) is the main technique that helps in diagnosis and is based on the benefits of molecular biology. However, it is also a very useful tool in research. There are two variants, endpoint PCR and real-time PCR. The first gives information on gene activation, while the second allows the use of RNA as a template, transcription reverse RNA to complementary DNA (cDNA) and provides information on the detection, characterization and quantification of acids nucleic.

The theory behind this technique is to provide a medium that includes a DNA polymerase, magnesium, nucleotides, oligonucleotides, the synthesized cDNA, and a thermocycler. Eventually, and after short periods of changes in temperature, double-stranded DNA goes to:

1) Denature (90°C): separation of the strands.
2) Alienate (50-65°C): union of the oligonucleotides to the single chain.
3) Extend (70°C): synthesis of a new strand, for 20-30 cycles.

The field of molecular biology continues to revolutionize as technology advances and provides us with more and more specific information in different areas of daily life.

References

Alberts, B.; Johnson, A.; Lewis J.; Raff M.; RobertsK. and Walter P.: Molecular Biology of the Cell. 6th ed. Omega Publisher. 2014.