TY - JOUR
T1 - Dendritic cytoskeletal protein expression in mental retardation
T2 - An immunohistochemical study of the neocortex in rett syndrome
AU - Kaufmann, Walter E.
AU - MacDonald, Shawna M.
AU - Altamura, Claudia R.
PY - 2000
Y1 - 2000
N2 - Many syndromes associated with mental retardation (MR) are characterized by cortical dendritic anomalies. Despite their morphological similarity, these changes appear to involve different stages of dendritic development. The neuronal cytoskeleton, which includes microfilaments, neurofilaments and microtubules, is essential for these developmental processes. Levels and phosphorylation of microtubule-associated proteins (MAPs), which stabilize microtubules, seem to determine different stages of dendritic formation with certain MAPs (e.g. MAP-2) appearing to mediate the effects of external modulators upon these processes. Early studies on neuronal cytoskeleton in MR, which have shown a selective reduction in MAP-2 expression, have focused on Rett syndrome (RS). Here, by a semiquantitative immunohistochemical analysis of the pericentral cortex, we examine the contribution of specific neuronal populations to these changes in cytoskeletal proteins. Decreased MAP-2 staining in RS was more marked in layers V-VI, while increased nonphosphorylated neurofilament immunoreactivity was found in layers II-III in RS. Age-related increases in dendritic MAP-2 immunoreactivity in layers V-VI were also absent in RS. The specificity of these cytoskeletal protein changes, their significance for RS pathogenesis and plasticity, as well as their implications for other MR-associated disorders, are also discussed.
AB - Many syndromes associated with mental retardation (MR) are characterized by cortical dendritic anomalies. Despite their morphological similarity, these changes appear to involve different stages of dendritic development. The neuronal cytoskeleton, which includes microfilaments, neurofilaments and microtubules, is essential for these developmental processes. Levels and phosphorylation of microtubule-associated proteins (MAPs), which stabilize microtubules, seem to determine different stages of dendritic formation with certain MAPs (e.g. MAP-2) appearing to mediate the effects of external modulators upon these processes. Early studies on neuronal cytoskeleton in MR, which have shown a selective reduction in MAP-2 expression, have focused on Rett syndrome (RS). Here, by a semiquantitative immunohistochemical analysis of the pericentral cortex, we examine the contribution of specific neuronal populations to these changes in cytoskeletal proteins. Decreased MAP-2 staining in RS was more marked in layers V-VI, while increased nonphosphorylated neurofilament immunoreactivity was found in layers II-III in RS. Age-related increases in dendritic MAP-2 immunoreactivity in layers V-VI were also absent in RS. The specificity of these cytoskeletal protein changes, their significance for RS pathogenesis and plasticity, as well as their implications for other MR-associated disorders, are also discussed.
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U2 - 10.1093/cercor/10.10.992
DO - 10.1093/cercor/10.10.992
M3 - Review article
C2 - 11007550
AN - SCOPUS:0033807656
SN - 1047-3211
VL - 10
SP - 992
EP - 1004
JO - Cerebral Cortex
JF - Cerebral Cortex
IS - 10
ER -