Ever since researchers connected the shortening of telomeres—
the protective caps on the ends of chromosomes—to aging and
disease, the race has been on to understand the factors that
govern telomere length. Salk Professor and holder of the Donald
and Darlene Shiley Chair Jan Karlseder, first author Teresa
Rivera and colleagues have found that a balance of elongation
and trimming in stem cells results in telomeres that are, as
Goldilocks would say, not too short and not too long, but just right.
The finding deepens our understanding of stem cell biology and
could help advance stem cell based therapies, especially related
to aging and regenerative medicine.
The Goldilocks effect in aging research
Findings highlight promise of chimeric
organisms for science and medicine
AS SEEN IN
The word “chimera” originally described mythological creatures
or deities in polytheistic religions. In science, an interspecies
chimera is an organism containing cells from different species.
Rapid advances in the ability to grow cells, tissues and organs
of one species within an organism of another species (forming
“chimeric” organisms) offer an unprecedented opportunity for
tackling longstanding scientific mysteries and addressing
pressing human health problems, particularly the need for
transplantable organs and tissues. The lab of Juan Carlos
Izpisua Belmonte combined cutting-edge gene-editing and
stem cell technologies to grow a rat pancreas, heart and eyes in
a developing mouse, providing proof-of-concept that functional
organs fromone species can be grown in another. The work marks
the first steps toward the generation of transplantable human
organs using large animals.
See microscopy from
this research on page 44