class 2 - 09_25_Chromosome22.jpg Hierarchy of gene...

Info iconThis preview shows pages 1–14. Sign up to view the full content.

View Full Document Right Arrow Icon
09_25_Chromosome22.jpg
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Hierarchy of gene organization Gene – single unit of genetic function Operon – genes transcribed in single transcript Regulon – genes controlled by same regulator Modulon – genes modulated by same stimilus Element – plasmid, chrom- osome,phage Genome ** order of ascending complexity
Background image of page 2
Polymorphic repeats Can be found anywhere in the genome The longer the repeat, the more polymorphic it is Are the basis for DNA fingerprinting & paternity testing In silico estimation of potentially polymorphic repeats suggest > 100,000 in the human genome
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Polymorphic repeats in genes Are found in genes less frequently Have been implicated in several inherited genetic disorders Mutations at a rate of up to 100,000x that of SNPs Have also been linked to roles in development, cancer & morphology
Background image of page 4
Human Genome Organization HUMAN GENOME Genes and gene- related sequences Extragenic DNA Nuclear genome 3000 Mb 65-80000 genes Mitochondrial genome 16.6 kb 37 genes Coding DNA Noncoding DNA Unique or low copy number Moderate to highly repetitive Pseudogenes Gene fragments Introns, untranslated sequences, etc. Tandemly repeated or clustered repeats Interspersed repeats Unique or moderately repetitive Two rRNA genes 22 tRNA genes 13 polypeptide- encoding genes 30% 70% 10% 90% 80% 20% From: Dr Finbarr Hayes lec
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
HUMAN NUCLEAR GENOME 24 chromosomes (haploid) 3200 Mbp 30,000 genes Mitochondrial genome 16569 bp 37 genes Human genome = nuclear genome + mitochondrial genome
Background image of page 6
H strand enriched in G L strand enriched in C
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Organization of the human genome Limited autonomy of mt genomes mt encoded nuclear NADH dehydrog 7 subunits >41 subunits Succinate CoQ red 0 subunits 4 subunits Cytochrome b-c1 comp 1 subunit 10 subunits Cytochrome C oxidase 3 subunits 10 subunits ATP synthase complex 2 subunits 14 subunits tRNA components 22 tRNAs none rRNA components 2 components none Ribosomal proteins none ~80 Other mt proteinsnone mtDNA pol, RNA pol etc.
Background image of page 8
Human Mitochondrial Genome Small (16.5 kb) circular DNA rRNA, tRNA and protein encoding genes (37) 1 gene/0.45 kb Very few repeats No introns 93% coding; Genes are transcribed as multimeric transcripts Recombination not evident Maternal inheritance
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
What are the mitochondrial genes? 24 of 37genes are RNA coding 22 mt tRNA 2 mit ribosomal RNA (23S, 16S) 13 of 37 genes are protein coding (synthethized on ribosomes inside mitochondria) some subunits of respiratory complexes and oxidative phosphorylation enzymes
Background image of page 10
Two overlapping genes encoded by same strand of mt DNA (unique example) Two independent AUG located in Frame-shift to each other, second stop codon is derived from TA + A (from poly-A)
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Mitochondrial codon table 22 tRNA cover for 60 positions via third base wobble
Background image of page 12
3200 Mb 23 (XX) or 24 (XY) linear chromosomes 30-35,000 genes 1 gene/100kb Introns in the most of the genes 1,5 % of DNA is coding Genes are transcribed individually Repetitive DNA sequences (45%) Recombination at least once for each chrom. Mendelian inheritance (X + auto, paternal Y)
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 14
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 10/07/2010 for the course DBT 446 taught by Professor Dd during the Spring '10 term at Indian Institute of Technology, Guwahati.

Page1 / 80

class 2 - 09_25_Chromosome22.jpg Hierarchy of gene...

This preview shows document pages 1 - 14. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online