Importance of Molecular Biology
Molecular biology is the study of structural and functional of macromolecules. It was related to the molecular basis of biological activity between biomolecules in the different method of a cell, including the interactions between DNA, RNA, Proteins, as well as the regulation of these interactions.
In 1938, Warren of the Rockefeller discovered Molecular biology and laid the foundation following them then James Watson and Francis Crick discovered the double helical structure of DNA molecules in 1953, and then only Francis Crick is called as a father of molecular biology.
The basic concept of molecular biology is a research predominantly devoted to the understanding of the structure and function of the protein and nucleic acids. That is the translation of DNA into protein.
The translation process is otherwise said to be a Gene expression. Expressing a gene means manufacturing its corresponding proteins, and this multilayered process has two major steps. The first step, information in DNA is transferred to messenger RNA(mRNA) molecules in this process is called as transcription. During transcription, the DNA of a gene cleave as a template for complementary base-pairing, and this an enzyme called RNA polymerase
Several techniques used in the field of molecular biology
- PCR- Polymerase chain reaction
- Expression cloning
- Gel electrophoresis
- Macromolecule blotting and probing
Three major steps are involved in it. These three steps are repeated for 30 to 40 cycles. The cycles are done on an automated cycler, a device which rapidly heats and cools the test tube containing the reaction mixture. The three steps
- Denaturation – at 94 C (201.2F), the double-stranded DNA melts and opens into two pieces of single-stranded DNA
- Annealing – Polymerase required a short sequence called a primer. “Anneal” to the strand of DNA at a temperature of 95 degrees centigrade, so the test tube is cooled to 45- 60 degrees C
- Extension – At 72 C (161.6 F), the polymerase works prime, and DNA building blocks complementary to the template are coupled to the primer, making a double-stranded DNA molecule
It is a technique in DNA cloning that uses expression vector to develop a library of clones, with each clone expression in one protein. If the protein of interest is an enzyme, it can be found by testing for its biochemical activity. A very familiar method for identifying a particular protein is by using antibodies, or immune globulins, that bind specifically to that protein. Expression cloning uses a cDNA library, in which protein-coding sequences are un-interrupted by introns. The mRNA can then be translated into protein.
It is a technique used to cleave the charged molecules like DNA, RNA, Protein. The separation of these molecules is achieved by placing them in a gel made up of small pores and setting an electric field across the gel. The molecules will move based on their inherent electric charge and smaller molecules will move faster than larger molecules; thus, a size separation is achieved within the pool of molecules running through the gel. The electrophoresis works to move the particles, using their inherent electric charge, through the sieve.
Macromolecule blotting and probing
It is a term that refers to the process of detecting the presence and quantity of DNA, RNA or protein in cells. There are three important types of blotting are Southern blotting, Northern blotting, and Western blotting
- Southern blotting - Southern blotting is an example of RFLP (restriction fragment length polymorphism). Southern blotting is a hybridization technique for identification of the particular size of DNA from the mixture of other similar molecules.
- Northern blotting – The Northern Blot is a technique used to study gene expression via mRNA transcripts. The northern blot was named after the southern blot, Which was developed to study DNA.
- Western blotting- Western blot is often used in research to separate and identify proteins.
- Arrays – It is a kind of data structure that can store a fixed-size sequential collection of elements. It is used to store a collection of data. An array is used to store a collection of data, but it is often more useful to think of an array as a collection of variables of the same type.
Plant biotechnology is a technology which is used to grow or regenerate the plants in an In-vitro method using any part of the plant tissues and organs with suitable nutrient medium and proper environmental condition. German Botanist Haberlandt is the father of Plant tissue culture.
Plant tissues, test tubes or plastic containers, sterile loop, burner, aseptic laboratory, Culture Medium (eg, MS medium- Murashige and Skoog medium), Laminar airflow chamber, Growth factor, etc.
Basic concept of plant tissue culture
It has two basic important methods (i.e) Plant cell culture/ organ culture and regenerating the plants
The process of plant cell culturing/ organ culturing
- Select any plant and take the section of any part of the plant eg,( shoot, root and meristem, axillary bud) and culture into the suitable medium (Murashige and Skoog medium) in an aseptic condition.
- The Plant should be in a sterile condition.
Regenerating the plants:
- After taking the section of the plant from the mother plant, place it into the test tube which contains the concerned medium. The medium should be in a sterile condition.
- This process should be held in an aseptic environmental condition.
- The plant section protocol should be done by using a laminar air flow chamber because it has an aseptic environment and the flow of chamber will protect the plant from microorganisms and fungal activity.
Plant biotechnology impact will also be used in an agriculture. The basic technology can be divided into five classes and they are callus, organ, meristem, protoplast and cell culture. The techniques are embryo, ovary, ovule, and anther.
Four different classifications of culture
- Embryo culture
- Anther and pollen culture
- Tissue and cell culture
- Apical meristem - find out in the youngest leaf measured about 100mm in diameter and 250 mm in length called apical meristem tip.
- Meristem tip - find out in the well mature leaf.
For the regenerative plants, an apical meristem leaf part is the best part to grow the plant using an in vitro method.
Embryo culture – For embryo culture, embryos are excised from immature seed or from the hood. The collected embryo is directly transformed into the culture plate or culture tube containing synthetic nutrient medium under laminar air flow chamber
Application – Recovery of distance hybrids.
Meristem Culture- It has two types they are named as Apical meristem tip and meristem tip.
Anther and pollen culture – Culturing of anther obtained from unopened flower bud in the nutrient medium under aseptic condition. Callus tissue or embryoids that give rise to haploid plantlets either through embryogenesis and organogenesis.
Pollen is otherwise said to be microspores. The microspores are developed into a haploid plantlet under the nutrient medium also which gives rise to either embryogenesis and Organogenesis.
Tissue and cell culture – The tissue or cell which is excised from any part of the plant like shoot, root, meristem, etc. It directly transformed into culturing dish or test tube containing a synthetic medium. This process should be held on an aseptic condition in laminar air flow chamber.
Growth of Plant
- 1st step- Growth of callus
- 2nd development of shoot and root
- 3rd Development of Apical meristem
- 4th Slowly transform the plant from lab temperature to surface temperature.