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Published on: March 11, 2011

Senescence-related functional nuclear barrier by down-regulation of nucleo-cytoplasmic trafficking gene expression

Sung Young Kim1, Sung Jin Ryu, Hong Ju Ahn

  • 1Department of Biochemistry and Molecular Biology, Aging and Apoptosis Research Center, Institute on Aging, Seoul National University College of Medicine, Seoul 110-799, South Korea.

Biochemical and Biophysical Research Communications
|November 12, 2009
PubMed

Insights

Senescent cells exhibit reduced responsiveness due to impaired nuclear transport. This study reveals that down-regulated nucleo-cytoplasmic trafficking genes create nuclear barriers in aging cells.

Area of Science:

  • Cellular senescence
  • Molecular biology
  • Aging research

Background:

  • Senescent cells are characterized by hypo-responsiveness to growth factors and apoptotic stimuli.
  • Key signaling pathways, including ERK1/2 and NF-kB, are involved in cellular responses.

Purpose of the Study:

  • To investigate the molecular mechanisms underlying hypo-responsiveness in senescent cells.
  • To identify changes in gene expression related to nuclear transport in aging cells.

Main Methods:

  • Microarray analysis to compare gene expression profiles between young and senescent human diploid fibroblasts (HDFs).
  • RT-PCR and Western blot to validate the expression levels of specific nucleo-cytoplasmic trafficking genes.

Main Results:

  • Senescent HDFs showed inhibited nuclear translocation of activated p-ERK1/2 and NF-kB p50.
  • Significant down-regulation of nucleo-cytoplasmic trafficking genes, including nucleoporins, karyopherins, and Ran-regulating factors, was observed in senescent cells.
  • Gene expression profiling revealed a vast reduction in these trafficking genes compared to young cells.

Conclusions:

  • Down-regulation of nucleo-cytoplasmic trafficking genes contributes to functional nuclear barriers in senescent cells.
  • These barriers may explain the hypo-responsiveness characteristic of cellular senescence.
  • Targeting these trafficking pathways could offer insights into aging and age-related diseases.

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