0:00
My
name is Michal Jazwinski,
I'm at Tulane University,
and today, I will be
discussing yeast studies on ageing.
0:09
During this talk, I will present
a brief history of yeast ageing
research and how this work
contributed to the understanding
that genes play a
major role in ageing.
I will discuss three concepts
that arose from early studies
of ageing using yeast as a model.
I will then show how these
concepts to encompass
the role of mitochondria in ageing,
the phenomenon of age asymmetry
as a cell quality control mechanism,
the impact of epigenetic regulation
of gene expression on ageing, and
the importance of genome stability
in ageing.
This talk will end
with a juxtaposition
of two different models
of ageing that are
widely used replicated lifespan
and chronological lifespan.
The impact of nutrient
limitation on ageing
is an obvious element
of consideration here.
Finally, the relevance
of examination
of the impact of natural genetic
variation on yeast ageing
will be considered.
1:02
In 1959, Mortimer and Johnston
published a brief letter
with one figure showing
that individual yeast cells
divide a limited number of times.
They are mortal.
Later, this finite life
span of dividing yeast cells
became known as the Replicated
Life Span, or RLS for short.
Interestingly, only two years later
in 1961, Hayflick and Morehead
showed that normal diploid
human fibroblasts have
a limit to their population
doubling levels,
another example of a finite
replicative life span.
The finding of Hayflick
and Morehead immediately
drew much attention because it
contested long-held beliefs.
