Plant genome projects aim to discover all the genes and their functions in a particular plant species. Early projects focused on model organisms like Arabidopsis thaliana due to their small genomes and amenability to genetic studies. In 1990, the National Science Foundation led a multi-agency effort to sequence the entire Arabidopsis genome by 2000, making it the first plant to be fully sequenced. Recent advances have enabled large-scale genome sequencing projects, like the 1001 Genomes Project which obtained complete genomes of 1001 Arabidopsis strains from different geographical regions to study genetic variations.
2. Plant Genome Project
A plant genome project aims to discover all genes and their
function in a particular plant species.
Initially Plant genome projects focused on a few model
organisms
Characterized by
Small genomes or their amenability to genetic studies
In 1990, NSF led a multi-agency, multinational project to
identify all the genes in Arabidopsis thaliana by the end of
2000
3. Arabidopsis thaliana was the first plant to be completely
sequenced
The flowering plant Arabidopsis thaliana is an important
model system for identifying genes and determining their
functions
Recent advances in DNA sequencing technologies have
dramatically reduced the cost and time needed to sequence
an organism's entire genome.
Large-scale sequencing projects have been undertaken to
take advantage of the speed and efficiency of next generation
DNA sequencing
4. In 2008, the 1001 Genomes Project was launched.
The project aimed to obtain the complete genome of 1001
strains of Arabidopsis from different geographical regions.
Eleven institutes participated in this project worldwide.
5. Introduction to Arabidopsis Thaliana
Arabidopsis thaliana also called the Thale cress, mouse-ear
cress or Arabidopsis.
Arabidopsis thaliana is an annual (rarely biennial) plant.
Small flowering plant native to Eurasia (Europe & Asia)
A. thaliana is considered a weed.
It is found by roadsides and in disturbed land.
It belongs to mustard family but have white flower.
6.
7. Arabidopsis – A Model Plant
Arabidopsis thaliana has basic similarities to most plants.
Short-generation time; 8 weeks from seed to seed.
Small plant (20 cm tall), easily grown at high density in
glasshouse or culture room.
Self fertilizes. A single plant produces hundreds or thousands
of seeds.
Small genome size (125 Mb, 5 chromosomes).
Simple organization of genome
8. Arabidopsis Model Genome Project
In 1990, NSF led a multi-agency, multinational project to
identify all the genes in Arabidopsis thaliana.
This included; saturating the genome with mutations,
identifying every essential gene, and sequencing the entire
genome by the end of the decade.
The Arabidopsis stock centers were established in 1991 to
preserve and distribute biological materials
There are two such centers—the Arabidopsis Biological
Resource Center (ABRC) at Ohio State University in Columbus,
and the Nottingham Arabidopsis Stock Centre (NASC) at the
University of Nottingham, United Kingdom
9. Arabidopsis Genome Initiative
In 1996 the Arabidopsis Genome Initiative (AGI) was establish to
facilitate coordinated sequencing of the Arabidopsis genome.
Three groups contributed to the work.
1. Genome Sequencing Groups (sequenced and annotated assigned
chromosomal regions).
2. Genome Analysis Group (carried out the analyses of the
sequenced regions).
3. Contributing Authors
Comparative analysis of the genomes of A. thaliana accessions.
Comparative analysis of the genomes of A. thaliana and other
genera
11. In 1998, physical maps of all chromosomes were completed.
In 1999, sequence and analysis of chromosomes 2 & 4
completed.
In 2000, sequence and analysis of chromosome 1, 3, & 5
completed and hence whole genome sequencing was
completed.
The Arabidopsis Genome Sequencing Project was officially
completed in late 2000
12. A. Thaliana Genome
Chromosomes : 5
Genome size : 146 Mb (Estimated)
Sequenced and annotated genome space : 119 Mb
Predicted protein coding genes : 26,207
Protein coding genes with identified transcripts : 19,117
Transposons and pseudogenes : 3,786
Distinct proteins : 27,855
13.
14. 1001 Genome Project
In 2008, 1001 genome project was launched In order to discover
the whole-genome sequence variations.
By investigating the genetic material of about one hundred strains
of this plant from different geographical regions, researchers found
a huge number of variations.
In addition to millions of small differences that lead to a diversity of
molecular gene products, they found hundreds of genes that are
missing in some strains or have extra copies in others.
It is probably this great flexibility within the genetic material that
makes this plant particularly adaptable.
15. TAIR – THE ARABIDOPSIS INFORMATION
RESOURCE
The Arabidopsis Information Resource (TAIR) maintains a database
of genetic and molecular biology data for the model higher plant
Arabidopsis thaliana.
TAIR is located at Phoenix Bioinformatics
Data available from TAIR includes:
The complete genome sequence,
Gene structure, gene expression & gene product information,
DNA and seed stocks, genome maps, genetic and physical markers,
Publications, and information about the Arabidopsis research
community
16. The Arabidopsis Biological Resource Center at The Ohio State
University collects, reproduces, preserves and distributes seed
and DNA resources of Arabidopsis thaliana and related
species
Resources are donated by researchers from around the world.
More than 100,000 samples are shipped annually to
researchers and educators from 60 countries.
Stock information and ordering for the ABRC are fully
integrated into TAIR