TY - JOUR
T1 - Deficiency of the Mre11 DNA repair complex in Alzheimer's disease brains
AU - Jacobsen, Elizabeth
AU - Beach, Thomas
AU - Shen, Yong
AU - Li, Rena
AU - Chang, Yung
N1 - Funding Information:
We thank Dr. D. Ramsden for providing anti-Mre11 antibody. We greatly appreciate technical support from Arizona State University W. M. Keck Lab for confocal microscopy. This work was partly supported by a NIH grant CA73857 (to Y.C.) and an Achievement Rewards for College Scientists Fellowship (to E.A.J.).
PY - 2004/9/10
Y1 - 2004/9/10
N2 - The hallmarks of Alzheimer's disease (AD) brains are deposition of Abeta plaques, appearance of neurofibrillary tangles, and extensive loss of neuronal cells. While Abeta plaques and neurofibrillary tangles play a significant role in the pathogenic dysfunction of neurons, factors that accelerate the neurodegenerating process remain to be defined. One set of factors examined in this study is the Mre11 protein complex, composed of Rad50, Mre11 and Nbs1. This protein complex plays an essential role in cellular responses to DNA damage, such as initiating cell cycle checkpoints and repairing damaged DNA. A defect in any component of this protein complex is detrimental to cells. Recently, several groups have observed abnormal cell cycle regulation and/or accumulated DNA damage in AD neurons. These pathological alterations could conceivably be caused or exacerbated by any compromise in the Mre11 complex. In this study, we compared the levels of the Mre11 complex proteins in brain samples from AD and age-matched non-dementia controls. We show for the first time that the Mre11 complex proteins are present in neurons of the adult human cortex and cerebellum. These proteins were found substantially reduced in the neurons of AD cortex. Our finding suggests that the loss of the Mre11 complex may be associated with the pathogenesis of AD.
AB - The hallmarks of Alzheimer's disease (AD) brains are deposition of Abeta plaques, appearance of neurofibrillary tangles, and extensive loss of neuronal cells. While Abeta plaques and neurofibrillary tangles play a significant role in the pathogenic dysfunction of neurons, factors that accelerate the neurodegenerating process remain to be defined. One set of factors examined in this study is the Mre11 protein complex, composed of Rad50, Mre11 and Nbs1. This protein complex plays an essential role in cellular responses to DNA damage, such as initiating cell cycle checkpoints and repairing damaged DNA. A defect in any component of this protein complex is detrimental to cells. Recently, several groups have observed abnormal cell cycle regulation and/or accumulated DNA damage in AD neurons. These pathological alterations could conceivably be caused or exacerbated by any compromise in the Mre11 complex. In this study, we compared the levels of the Mre11 complex proteins in brain samples from AD and age-matched non-dementia controls. We show for the first time that the Mre11 complex proteins are present in neurons of the adult human cortex and cerebellum. These proteins were found substantially reduced in the neurons of AD cortex. Our finding suggests that the loss of the Mre11 complex may be associated with the pathogenesis of AD.
KW - Cell cycle checkpoint
KW - DNA damage recognition and repair
KW - Genome instability
KW - Mre11 protein complex
KW - Neurodegeneration
KW - Post-mitotic neurons
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U2 - 10.1016/j.molbrainres.2004.05.023
DO - 10.1016/j.molbrainres.2004.05.023
M3 - Article
C2 - 15337312
AN - SCOPUS:4344622376
SN - 0169-328X
VL - 128
SP - 1
EP - 7
JO - Molecular Brain Research
JF - Molecular Brain Research
IS - 1
ER -