Biological complexity: control of aging (Introduction)

by David Turell , Wednesday, December 28, 2022, 18:03 (486 days ago) @ David Turell

Complex molecular mechanisms with controlled autophagy:

https://phys.org/news/2022-12-scientists-uncover-cellular-mechanism-aging.html

"Research at the Institute of Molecular Biology and Biotechnology (IMBB) of the Foundation for Research and Technology-Hellas (FORTH), published today in the journal Nature Aging, reveals a fundamental quality control mechanism that operates in cells to safeguard the integrity and function of the nucleus. By maintaining nuclear homeostasis, this molecular mechanism contributes critically to promote longevity and fertility.

"IMBB researchers ... discovered that recycling of nuclear and nucleolar components via autophagy delays aging of somatic cells, and sustains the immortality of germ cells, which are required for reproduction.

***

"'We decided to focus on nuclear morphology in somatic cells, which deteriorates during aging. By contrast, the overall architecture of the nucleus is preserved in the germline. Our hypothesis was that a homeostatic mechanism effectively maintains the structure of germ cell nuclei, whereas it fails during aging, in the soma. We were surprised to find that autophagic recycling of nuclear material is an important factor, that preserves nuclear architecture and restricts nucleolar size. Interestingly, nucleophagy interfaces with nodal, pro-longevity signal transduction pathways, highlighting the complex crosstalk of the molecular mechanisms that influence aging,"

"The new study uncovers nucleophagy as a molecular mechanism by which diverse physiological signals are integrated to impact nuclear architecture and homeostasis. Furthermore, it identifies nucleophagy as a downstream effector of low insulin/IGF1 signaling and dietary restriction on somatic aging. Nesprin family members serve as key regulators of nucleophagy. Impairment of nuclear material recycling via nucleophagy diminishes stress resistance, undermines animal longevity and triggers progressive germline mortality.

"Therefore, nucleophagy is an essential soma longevity and germline immortality mechanism that promotes youthfulness and delays aging under conditions of stress, by preserving nuclear architecture and preventing nucleolar expansion. The tight evolutionary conservation and ubiquitous expression of the regulatory factors involved, indicate that similar pathways may govern aging in humans."

Comment: we see various aging patterns in animals from a few weeks in butterflies to 100 years in giant tortoises. Since all living forms eventually die, this is the complex control mechanism. Aging had to be designed from the beginning/origin of each form. How do you evolve an average time of death?