measuring ageing Flashcards
whats Gompertz’ law?
mortality increases with age, every 8 years mortality risk doubles
what has the most power over ageing ?
genetics - mice live longer than humans
what does Harvath clock relate to ?
rate of ageing and methylation
whats extrinsic mortality ?
risk of dying of something other than ageing
why isnt ageing selected for?
only matter to get the individual to survive to reproduce thats why humans begin to age after 40
whats the antagonist pleiotropy mutation theory ?
mutations arise and those which turn out to have negative effects in the long term but positive in the short term are selected for cause the individual lives long enough to reproduce
what are the issues with increasing age?
methods which induce increase in age may cause other health issues - reduced fitness/fertility
what is the disposal soma theory ?
germline is immoral but soma cells arent . animals divide up energy between progeny production or long term survival - life history
how can measure yeast reproduciton ?
mother cell has a scar from when the daughter cell has divided.
how does an old mother yeast cell not produce an old daughter cell?
has an age barrier between the two cells when they are connected - stops ageing macromolecules from passing over
what are examples of the ageing macromolecules?
senescence factors, extra chromosomal ribosomal dna circles and damaged proteins
how does forward/ classical genetics work ?
mutagenise germ-line then scan offspring for muts ( F2 for recessive muts) then map for the genes changed
how does reverse genetics work?
find a gene of interest then mut it, characterise phenotype produced to work out function of gene
what does EMS do ?
chemcial mutagenesis - random muts induced
what life stage do c. elegans go into if there is a lack of food in L1 ?
diapause daucer phase
what is DAF 2?
insulin like receptor
what is DAF16?
foxotranscription factor
when can DAF16 enter the nucleus ?
when it isnt pp and this cause the animal to live longer
when are mutations normally visible ?
F2 - homozygous and recessive
how do you work out which gene has mutated?
map to see how its inherited, cross it to see if it is similar with other mutants, - genetic linkage see how similar to see where on the chromosome it is
what are the two daucer mutants ?
DAFC adn DAFD
what does DAFC do ?
forms dauer - DAF2 +23
what does DAFD do ?
doesnt form dauer daf 16+18
what is epistasis analysis ?
work out if one gene is dependant on another
example of epistasis ?
daf 16 hides the effect of daf 2 therefore daf2 is upstream of daf 16 gene
what is non complementation ?
when you cross two genes and they produce a homologous phenotype
how do you narrow down where a gene is on a chromosome ?
use deletion mutants
what is Daf2 a homolog to ?
human igf/insulin receptor
what happens when insulin binds to the igf/insulin receptor ?
causes autophosporylation on tyrosine receptors
what do pp tyrosine attract?
AAP1 adaptor