Organization of genome presentation submitted by Divya choudhary under Dr. Harchand R DAGLA ( department of botany) Jai Narain Vyas University jodhpur

1. JAI NARAIN VYAS UNIVERSITY JODHPUR
Seminar topic – organization of genome
Submitted to -:
Dr. Harchand R.
Dagla
Submitted by -:
Divya
Department of botany

2. ORGANIZATION OF GENOME
Gene basic physical or functional unit of heredity.
its control a character. It transmits the character of from parents to their offspring
A gene is a segment of DNA that specifies the sequence of amino acids in
polypeptide chain.
Gene is present in the chromosome of the nucleus or extra chromosome of the
nucleus or extra chromosome DNA .
A gene may exist in alternative forms called alleles.

3. HISTORY
Gene was coined by Wilhelm Johansen
Gene theory was proposed by T. H. Morgan in 1911
The fine structure of gene was proposed by ‘ Seymour benzere’ in
1962.
Gene concept was given by ‘Sutton’

4. SPECIFIC FEATURES OF GENE
• The term gene is often used to refer genetic material on the chromosome
that code for a trait .
• Example one person has a gene for hair colour.
• It is a unit of recombination or capable of undergoing crossover.
• A unit of heredity connected with somatic structure or functional that lead
to a phenotype expression.
• A gene is the basic physical and functional unit of heredity.

5. BASIC STRUCTURE OF GENE
• Promoter:- region of gene where RNA polymerase bind
• Start :- Transcription beings
• Stop :- Transcription ends.
• Regulatory sites :- near the promoter where regulatory proteins
bind ( two gene on/off)

6. STRUCTURE OF GENE
• On the basis of structure of gene is the classification of two
type
1. prokaryotic gene
2. eukaryotic gene

7. PROKARYOTIC GENE
• Prokaryotic gene is composed of three regions
1. promoter region
2. RNA recording sequence
3. Terminator region
prokaryotic gene is continues and uninterested where there is no intron present
The reason 5’ of the promoter sequence is called upstream sequence and reason
3’ of the Terminator sequence is called downstream sequence

8. PROMOTER REGION
• This is situated on the upstream of the sequence that codes for RNA .
• Promoter region provide the location and direction of initiate transcription.
• At -10 there is a sequence TATAAT or PRIBNOW BOX.
• At -35 another consensus sequence TTGACA
RNA CODING SEQUENCE
• The DNA sequence that will become copied into an RNA molecule ( RNA
transcript)
• Starts with an initiator codon and ends with termination codon .
• No introns
• Collinear to it’s m-RNA

9. TERMINATOR REGION
• The region that signal the RNA polymerase is to stop transcription
from DNA template.
• transcription termination occur through RHO dependent or RHO
independent manner

10. EUKARYOTIC GENE STRUCTURE
• Eukaryotic gene are complex structure compare that prokaryotic gene
• They are composed of following region -:
• exons
• intron ,
• promoter sequence ,
• Terminator sequence,
• Upstream sequence,
• downstream sequence,
• Enhancers and silencers
• Signals ( upstream sequence signal for addition of cap and downstream sequence signal for
addition of poly a tail)

11. EXONS
• Coding sequence transcribed and translated coding for amino acid in
the polypeptide chain.
• Very in number sequence and length.
• A gene start and end with exon ( 5’ to 3’)
• Some exons include translated (UTR) region.
INTRONS
• Coding sequence is separated by non coding sequence called introns.
• They are removed when the primary transcript is processed to give the mature
RNA.
• All introns share the base sequence GT in the 5’ end and AG in the 3’ end.

12. PROMOTERS :-
• Promoter is regulator region of DNA located upstream controlling gene
expression.
• CORE PROMOTER:- transcription start site (-35) binding site for RNA
polymerase and it is a general transcription factor binding site.
• PROXIMAL PROMOTER :- Contain element. primary regulatory elements.
• These together and responsible RNA polymerase for binding of RNA
polymerase 2nd which is responsible for the transcription.

13. • Upstream 5’ End) :-
• 5’ UTR serve several functions including m-RNA transport and inhibitions of translation
• Signal. For addition of of Cap (7 methyl I guanosine) to 5’ end and of the mRNA
• The cap facilitates the inhibition of translation.
• Stabilization of mRNA.
• Downstream. 3’End):-
• 3 UTR Serve to add .mRNA-
• Stability and attachment site for poly-A-tail.
• The translation termination codon TAA.
• AATAR Sequence signal for addition of poly A tail.
• Terminator:-
• Recognized by RNA polymerase as a signal to stop transcription.
• Enhancer:-
• Enhances the transcription. of a gene upto few thousand bp upstream
• Silencers:-. Reduce Or Shut down the expression a near by gene

14. FUNCTION OF GENE
• Some genes encode for protein other encode for t-RNA, r-RNA etc.
• gene control the function of DNA and RNA
• Gene code for m-RNA, m-RNA code for protein.
• The sequence of genes encoding for the protein directly determines ,
their functions ( amino acid sequence)