Chloroplast DNA in Molecular Systematics Chloroplast organelle found
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Chloroplast DNA in Molecular Systematics
Chloroplast - organelle found in plant cells and eukaryotic algae - Photosynthesis
Chloroplast genome - Chloroplast DNA (cp. DNA) is also known as plastid - DNA (pt. DNA). Circular double stranded DNA molecule Chloroplast genome size ranges 120 -217 kb with majority of plants fall into 120 -160 kb. (Pelargonium has a chloroplast genome size 217 kb) contain about 100 genes to synthesize proteins cp. DNA regions includes Large Single-Copy (LSC) & Small Single-Copy (SSC) regions, and Inverted Repeats (IRA & IRB). Conifers and a group of legumes lack Inverted Repeats.
LSC IRA SSC IRB
Chloroplast genome - Complete chloroplast DNA sequences of four land - plants (Nicotiana tabacum, Marchantia polymorpha, Oryza sativa and Epifagus virginiana) were available for comparative study on structure and gene content of chloroplast genomes in 1980 s. At present, the number of complete chloroplast genome sequences is 122 (from 114 different organisms). eg. Arabidopsis thaliana, Coffea arabica, Eucalyptus globulus, Glycine max, Gossypium hirsutum, Helianthus annuus, Lycopersicon esculentum, Nymphaea alba, Phaseolus vulgaris, Pinus koraiensis, Piper cenocladum, Solanum tuberosum, Triticum aestivum, Vitis vinifera, Zea mays etc.
Characteristics of Chloroplast Genome - cp. DNA is a relatively abundant component of - - plant total DNA, thus facilitating extraction and analysis. Conservative rate of nucleotide substitution enables to resolve plant phylogenetic relationships at deep levels of evolution. eg. familial level; mono- & dicotyledonous; Chloroplast protein-coding genes evolve at a rate that is on average fivefold slower than plant nuclear genes.
Characteristics of Chloroplast Genome - Strictly maternally inherited in most - angiosperms while in conifers, inheritance is paternal. Chloroplast DNA is passed on from one generation to the next with only an occasional mutation altering the molecule; sexual recombination does not occur.
Molecular Systematics on cp. DNA - cp. DNA regions can be amplified by means - of PCR. The resulted PCR products may be subjected to RFLP or DNA sequencing. Common cp. DNA regions used in systematic study: rbc. L (1400 bp), trn. L-trn. F (250 -800 bp), atp. Brbc. L (1000 bp), trn. L intron (300 bp), mat. K (2600 bp), trn. T-trn. L (400 -800 bp), 16 S (1400 bp), rpo. C (3600 bp) etc.
LSC atp. B-rbc. L rpo. C trn. T-trn. L intron trn. L-trn. F mat. K IRA SSC IRB 16 S
Molecular Systematics on cp. DNA - Restriction site mapping of the entire chloroplast genome. (involve the isolation of chloroplast DNA from the total DNA) The whole chloroplast genomes of different Brassica species were digested with Sac. I
Molecular Systematics on cp. DNA - Singular structural rearrangements (e. g. - inversions and intron losses). Loss of intron of rpl 2 gene was found in species of order Caryophyllales (cacti, amaranths, carnations, carnivorous plants).
Molecular Systematics on cp. DNA - On of the most comprehensive phylogenetic - study of cp. DNA rearrangement involved a 22 kb inversion found to be shared by 57 genera representing all tribes of the family Asteraceae (sunflowers), a large plant family with 20, 000 species and 1100 genera. 50 kb inversion brought psb. A closer to rbc. L in legumes. 25 kb inversion brought atp. A closer to rbc. L in wheat.
H. subalata 96 H. nervosa H. dyeri Dryobalanoides clade Subsection Sphaerocarpae H. dryobalanoides H. pubescens Tree length = 143 CI = 0. 8811 RI = 0. 8651 92 51 H. mengerawan H. pierrei H. latifolia 75 Subsection Dryobalanoides H. beccariana 72 100 72 -bp deletion in the trn. L-trn. F H. myrtifolia H. ferruginea 89 H. sangal H. nutans H. odorata 69 Subsection Hopea H. helferi Hopea clade 84 D r y o b a l a n o i d e s H. apiculata H. bilitonensis Subsection Pierrea H o p e a H. wightiana Neobalanocarpus heimii Upuna borneensis Outgroup Phylogeny based on the trn. L-trn. F, trn. T-trn. L and atp. B-rbc. L sequences.
- Traditional systematics
- Systematics deals with
- Systematics vs taxonomy
- Section 2 modern classification
- Synapomorphy
- Covalent bond melting point
- Giant molecular structure vs simple molecular structure
- Zinc oxide + nitric acid → zinc nitrate + water
- Where is dna found
- What is the str found within this dna sequence
- Molecular scissors that "cut' dna *
- Chapter 12 section 1 dna the genetic material
- Replication fork
- Bioflix activity dna replication nucleotide pairing
- What are the enzymes involved in dna replication