How is the dilute gene inherited in the dogs?
it must be homozygous recessive
What mutation caused it?
nonsense mutation (G to A)
Role of MYO5A?
myosin motor that walk down the actin fiber and carries the melanosome cargo
Role of Rab27A?
on the surface of mature melanosomes, links to myosin motor MLPH and recruits melanophillin
Role of MLPH?
links Rab27A carrying the melanosomes to MYO5A
What are macromelanosomes?
clumps of pigment or concentrations of pigment
Do macromelanosomes cause dilute or dark fur?
They cause dilute fur due to the clumping of the pigment
Where else has MLPH caused dilution?
cats, humans, and mice
What exon was the mutation in in cats?
exon 2
What did the mutation in humans cause?
caused Griscelli syndrome, a pigment dilution disorder
Why didn’t the SNPs in exon 2 and 7 explain the phenotype?
never found a single mutation that would account for all the dog breeds, so unable to really pinpoint a direct solution
Where is the start codon in the gene?
the start of exon 2
What is a haplotype?
traits that are inherited together
Where is the SNP that causes the phenotype and why is its location significant?
it is at the splice site prior to exon 2
What is U1 protein?
-member of the spliceosome
-less effective without SF2/ASF
-binds to 5’ splice site
What is SF2/ASF?
-recruits U1
-abolished in the mutant
-ASF binds mRNA to the splice site
What is nonsense mediated decay?
-surveillance pathway that exists in all eukaryotes
-reduces errors in gene expression by eliminating mRNA transcripts that contain premature stop codons
What are the use of TAQMan probes?
they can identify a specific gene you want to measure
Special part of a TAQMan probe?
There is a quencher and a fluorescence area that when bound do not light up but when split apart via a polymerase they light up
When do you need to look at the samples in a qRT-PCR?
at the exponential phase to see the fluorescence the best