M Pharm Pharmacognosy Semester 2, MEDICINAL PLANT BIOTECHNOLOGY UNIT 1, Introduction to Plant biotechnology: Historical perspectives, prospects for development of plant biotechnology as a source of medicinal agents. Applications in pharmacy and allied fields. Genetic and molecular biology as applied to pharmacognosy, study of DNA, RNA and protein replication, genetic code, regulation of gene expression, structure and complicity of genome, cell signaling, DNA recombinant technology.

1. MEDICINAL PLANT
BIOTECHNOLOGY
S. PRITHIVIRAJAN., M. Pharm
Dept. of Pharmacognosy, COP,
Madurai Medical College,
Madurai-20
M PHARM - PHARMACOGNOSY SEM 2 UNIT 1

2. CONTENTS
 Introduction
 Historical Perspective•
 Prospects for Development
 Application in Pharmacy and Allied fields
 Genetic and Molecular Biology
 Study of DNA, RNA, Protein Replication
 Genetic codeRegulation in Gene Expression
 Structure and Complicity of Genome
 Cell Signaling
 DNA Recombinant Technology.

3. INTRODUCTION
Biotechnology is the controlled use of biological agents, such as micro-
organisms or cellular components, for beneficial use.
Plant Biotechnology describes a precise process in which scientific techniques
are used to develop useful and beneficial plants.
HISTORY PERSPECTIVES
• Matthias Schlieden and Theodor Schwan proposed the concept of Cell Theory
in the 19 century.
• Gottlieb Haberlandt, a German bolarist proposed the PatieIn 1981, scientist at
Ohio university proposed the first Transgenic Genes from the other animals into
mice.
• In 1980, Genetic Engineering was first used.

4. PROSPECTS FOR DEVELOPMENT OF BIOTECHNOLOGY (OBJECTIVES)
• 70-80% of people worldwide believe & turn to traditional herbal medicines.
• The global demand for herbal medicine is growing gradually
• Various technologies-adopted for enhancing bioactive molecules in medicinal plants.
• Biotechnological tools are important for the multiplication and genetic enhancement
of medicinal plants.
• Molecular biology, enzymology, and fermentation technology of plant cell cultures-
these systems may become a viable source of important secondary metabolites.
• DNA manipulation is resulting in relatively large amounts of desired compounds
produced by plants infected with an engineered virus.
• Combinatorial biosynthetic strategies are expected to utilized for important classes of
natural products, including alkaloids, terpenoids, and flavonoids.
• Several genes from different Taxus species are responsible for steps in biosynthesis.
It is building a basis for today's combinatorial biosynthesis.

5. APPLICATION OF BIOTECHNOLOGY IN PHARMACY AND ALLIED FIELD
Pharmaceutical biotechnology is a relatively new and growing field in which the
principles of biotechnology are applied to the development of drugs.
A majority of therapeutic drugs in the current market are bio formulations, such as
antibodies, nucleic acid products, and vaccines.
1. Production of Antibodies
• Plants now have potential as a virtually unlimited source of mAbs, referred to by
some as 'plantibodies'.
• Tobacco plants have been used extensively for antibody expression systems, other
plants have been used including potatoes, soybeans, alfalfa, rice, and corn.
2. Production of Vaccines
• The plant species to be used for the production and delivery of an oral vaccine.
Corn, is a good candidate for vaccine production for Animals.

6. • In humans, particularly infants,the plant of choice is the banana. Cereals and
other edible plants are more advantageous than tobacco for vaccine production.
• The wide variety of other therapeutic agents also have been derived.
Eg: Hepatitis – Interferon α ; Anemia - Erythropietin
GENETIC & MOLECULAR BIOLOGYAPPLIED TO PHARMACOGNOSY
Genetics and Molecular biology are field of biology studies the structure and
function of genes at a molecular level and thus employs methods of both molecular
biology and genetics.
The study of chromosomes and gene expression of an organism can give insight into
heredity, genetic variation, and mutations. Some of the major applications are,

7. 1. Cultivar Identification:
• PCR related methods
• DNA barcoding technology has enormous potential for cultivar identification.
• It was reported that APAPD and MARMS methods identified five kinds of Panax
Ginseng- related species.
2. Resource Protection
• The information on genetic diversity could guide the protection and development
of medicinal resources, especially the rare and endangered ones.
• Cistanche Deserticola and Cistanche Tubulasa, two endangered medical plants,
provided evidence for the protection of wild resources.
3. Formation mechanism of medicinal materials with good quality
• The quality of medicinal materials is highly affected by their genetic basis and
ecological environment.
• Helpful for Molecular breeding and cultivation of medicinal materials

8. 4. Production of active compounds
• Transgenic technology has been successfully used to obtain transgenic medicinal
plants Which have either disease, insect, drought, and salinity resistance, or have
higher production of active compounds.
• The production of tanshinone was obtained from hairy roots and suspension cells
of Salvia miltiorrhiza.
STUDY OF DNA
The structure of DNA is a double-helix polymer, a spiral consisting of two DNA
strands wound around each other. The breakthrough led to significant advances in
scientists’ understanding of DNA replication and hereditary control of cellular
activities.
 Each strand of a DNA molecule is composed of a long chain
of monomer nucleotides. The nucleotides of DNA consist of a deoxyribose sugar
molecule to which is attached a phosphate group and one of four nitrogenous bases:
two purines (adenine and guanine) and two pyrimidines (cytosine and thymine).

9.  The nucleotides are joined together by covalent bonds between the phosphate of
one nucleotide and the sugar of the next, forming a phosphate-sugar backbone from
which the nitrogenous bases protrude.
 One strand is held to another by hydrogen bonds between the bases; the sequencing
of this bonding is specific—i.e., adenine bonds only with thymine, and cytosine only
with guanine. A segment of DNA that codes for the cell’s synthesis of a
specific protein is called a gene.
 The configuration of the DNA molecule is highly stable, allowing it to act as a
template for the replication of new DNA molecules, as well as for the production
(transcription) of the related RNA (ribonucleic acid) molecule.
STUDY OF RNA
The RNA, abbreviation of ribonucleic acid, complex compound of high molecular
weight that functions in cellular protein synthesis and replaces DNA (deoxyribonucleic
acid) as a carrier of genetic codes in some viruses.

10.  RNA consists of ribose nucleotides (nitrogenous bases appended to a ribose sugar)
attached by phosphodiester bonds, forming strands of varying lengths. The
nitrogenous bases in RNA are adenine, guanine, cytosine, and uracil, which
replaces thymine in DNA.

11. Type Role
Messenger RNA (mRNA)
Carries information from DNA in the
nucleus to ribosomes in the cytoplasm
Ribosomal RNA (rRNA) Structural component of ribosomes
Transfer RNA (tRNA)
Carries amino acids to the ribosome
during translation to help build an amino
acid chain
TYPES OF RNA
PROTIEN SYNTHESIS
DNA and RNA nucleotide sequences to be translated into the amino acids Genes
that provide instructions for proteins are expressed in a two-step process.
They are,
1. Transcription 2.Translation

12. •In Transcription, the DNA sequence of a gene is "rewritten" using RNA
nucleotides. In eukaryotes, the RNA must go through additional processing steps
to become a messenger RNA, or mRNA.
•In Translation, the sequence of nucleotides in the mRNA is "translated" into a
sequence of amino acids in a polypeptide (protein or protein subunit).

13. THE GENETIC CODE
During translation, the nucleotide sequence of an mRNA is translated into the amino
acid sequence of a polypeptide. Specifically, the nucleotides of the mRNA are read in
triplets (groups of three) called codons.
There are totally 64 codons, where 61 codons that specify amino acids. One codon is
a "start" codon that indicates where to start translation. The start codon specifies the
amino acid methionine, so most polypeptides begin with this amino acid. Three other
“stop” codons signal the end of a polypeptide.
Codons in an mRNA are read during translation, beginning with a start codon and
continuing until a stop codon is reached. mRNA codons are read from 5' to 3' , and they
specify the order of amino acids in a protein from N-terminus (methionine) to C-terminus.
These relationships between codons and amino acids are called the genetic code.

14. REGULATION OF GENE EXPRESSION
• Gene is a section of DNA with the information to construct a protein.
• Gene expression is the process by which information from a gene is used in the
synthesis of a functional gene product that enables it to produce such as
protein/noncoding RNA.
• Steps involved in gene expression are Transcription and Translation together it is
called Gene expression.
The following is a list of stages where gene expression is regulated,
1. Signal transduction - The process by which a chemical or physical signal is
transmitted through a cell as a series of molecular events.
2. Chromatin remodeling - The dynamic modification of chromatin architecture to
allow access of condensed genomic DNA to the regulatory transcription
machinery proteins, and thereby control gene expression.
3. Transcription
4. Translation

15. STRUCTURE AND
COMPLICITY OF
GENOME
CONTINOUS TO NEXT PAGE

17. CELL SIGNALING
Cell signaling is the fundamental process by which specific information is
transferred from the cell surface to the cytosol and ultimately to the nucleus, leading
to changes in gene expression.
Cell signalling takes place in the following three stages:
• Binding of the signal molecule to the receptor.
• Signal transduction, where the chemical signals activate the enzymes.
• Finally, the response is observed
Intracellular Receptors
Intracellular receptors are common types of cell signaling receptor located
within the cell in the cytoplasm. The intracellular receptors are of two types:
1. Nuclear receptors
2. Cytoplasmic receptors
Nuclear receptors are special classes of proteins with diverse DNA binding
domains that form a complex with thyroid hormones that enter the nucleus and
regulate the transcription of a gene.

18. DNA RECOMBINANT TECHNOLOGY
The process involves the introduction of a foreign piece of DNA structure into the
genome which contains our gene of interest. This gene which is introduced is the
recombinant gene and the technique is called Recombinant DNA technology.
Tools Of Recombinant DNA Technology
The enzymes which include the restriction enzymes help to cut, the polymerases-
help to synthesize and the ligases- help to bind. The restriction enzymes used in
recombinant DNA technology play a major role in determining the location at which the
desired gene is inserted into the vector genome.
Process of Recombinant DNA Technology
Step-1. Isolation of Genetic Material
The first and the initial step in Recombinant DNA technology is to isolate the desired
DNA in its pure form i.e. free from other macromolecules.

19. Step-2.Cutting the gene at the recognition sites.
The restriction enzymes play a major role in determining the location at which the
desired gene is inserted into the vector genome. These reactions are called ‘restriction
enzyme digestions’.
Step-3. Amplifying the gene copies through Polymerase chain reaction (PCR).
It is a process to amplify a single copy of DNA into thousands to millions of
copies once the proper gene of interest has been cut using restriction enzymes.
Step-4. Ligation of DNA Molecules.
In this step of Ligation, the joining of the two pieces – a cut fragment of DNA and
the vector together with the help of the enzyme DNA ligase.
Step-5. Insertion of Recombinant DNA Into Host.
In this step, the recombinant DNA is introduced into a recipient host cell. This
process is termed as Transformation. Once the recombinant DNA is inserted into the
host cell, it gets multiplied and is expressed in the form of the manufactured protein
under optimal conditions.

20. Application of Recombinant DNA Technology
• Gene Therapy – It is used as an attempt to correct the gene defects which give rise
to heredity diseases.
• Clinical diagnosis – ELISA is an example where the application of recombinant
• Recombinant DNA technology is widely used in Agriculture to produce genetically-
modified organisms such as Flavr Savr tomatoes, golden rice rich in proteins, and
Bt-cotton to protect the plant against ball worms and a lot more.
• Recombinant DNA technology enables develop vaccines by cloning the gene used
for protective antigen protein. Viral vaccines, through this technology, for example,
Herpes, Influenza, Hepatitis, and Foot and Mouth Disease
• In Industry-production of chemical compounds of commercial importance,
improvement of existing fermentation processes, and production of proteins from
wastes, also used for the production of Insulin.