What is attP sites in Drosophila?
Conveniently, attP sites have been identified on the major Drosophila chromosomes that satisfy these criteria (1). In practice, the landing sites attP18 (X chromosome), attP40 (2nd chromosome) and attP2 (3rd chromosome) might justifiably be considered the default choices for transgene insertion on these chromosomes.
What is attB and attP?
The attP site consists of a 234-bp DNA fragment containing five scattered putative Int-binding sites (4) whereas the attB site requires only a 16-bp sequence to be functional. The mv4 minimal attB site is the shortest attB sequence described to date.
Why Drosophila melanogaster is a model organism?
Due to their small size and minimal requirements, many Drosophila can be raised and tested within a small laboratory which does not have access time, space or funding. Genetic factors also make this fly an ideal model organism. D. melanogaster only has four pairs of chromosomes compared to 23 pairs in humans.
How do you make transgenic flies?
These steps include: 1) Prepare DNA that will be incorporated into the fly genome, 2) Prepare fly embryos, 3) Inject fly embryos with DNA, 4) Breed flies, 5) Select transgenic offspring, and 6) Examine light output from transgenic adults.
What is an attP site?
The attP site (5′-GTGCCCCAACTGGGGTAACCTttGAGTTCTCTCAGTTGGGGG-3′) is one of the two target sites of the phiC31:int integrase. phiC31:int mediates recombination between two non-identical target sites, attP and attB, each of which contains a short integration core flanked by imperfect inverted repeats.
What is attP phage?
Notes. In the free phage, the att site is referred to as attP (phage attachment site) while the corresponding site in a host genome is called attB (bacterial attachment site). After integration occurs to create a prophage, these sites are then known as attL (left end of prophage) and attR (right end of prophage).
What does ATTB mean?
ATTB
| Acronym | Definition |
|---|---|
| ATTB | Advanced Technology Transit Bus |
| ATTB | Age Tendre et Tête de Bois (French: Tender Age and Wooden Head; online forum) |
| ATTB | Ass to the Blast |
| ATTB | Association pour Techniques Thermiques de Belgique (French: Thermal Technology Association of Belgium) |
How many genes do Drosophila have?
The Drosophila melanogaster complete genome sequence was published in 2000. It contains 180 Mb (one third of which is centric heterochromatin) and approximately 14,000 protein-coding genes.
How many chromosomes are in Drosophila melanogaster?
Drosophila melanogaster flies have 4 chromosomes.
What are transgenic flies?
Scientists use transgenic organisms, which contain DNA that scientists inserted in the organisms’ genomes, to research many biological processes. In this lab, students produce and conduct experiments with virtual versions of transgenic Drosophila fruit flies.
What is a transgenic line?
The generation of a zebrafish transgenic line allows the expression of exogenous coding sequences (CDS) (e.g. transcription factors, CDS of human genes, fluorescent reporters, sensors to test environmental changes, optogenetic tools) under the control of tissue-specific promoters.
What does genetic recombination do?
Recombination is a process by which pieces of DNA are broken and recombined to produce new combinations of alleles. This recombination process creates genetic diversity at the level of genes that reflects differences in the DNA sequences of different organisms.
How to target transgenic constructs to specific genomic sites in Drosophila?
Here, we introduce a method for the precise targeting of transgenic constructs to predetermined genomic sites in Drosophila using the φC31 integrase system in conjunction with recombinase-mediated cassette exchange (RMCE).
Is recombination limited to the attP and attB sequences?
Importantly, we observed no structural changes either in the cassette itself or in flanking genomic DNA, indicating that recombination was limited to the attP and attB sequences as expected.
What happens when attP/attB pairs are aligned with a target cassette?
We predicted that recombination between the two attP/attB pairs on either side of a target cassette aligned with a donor cassette would result in a clean exchange of the mini-whiteand yellowcassettes, converting the w+y−parental phenotype to w−y+(Figure 1).
Is it possible to perform RMCE with attP and attB sequences?
RMCE using attP and attB sequences in direct orientation is also possible in Drosophila (A. L ee and J. B ateman, unpublished observations), but this strategy can result in the incorporation of the plasmid backbone rather than the donor cassette when a visible marker is not used. In contrast, RMCE via inverted attP…