Genotype and phenotype analysis of two patients with Williams syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To perform genetic analysis for two patients with supravalvular aortic stenosis and unusual facial features.</p><p><b>METHODS</b>Cytogenetic and molecular genetic methods including chromosome karyotyping, multiplex ligation-dependent probe amplification (MLPA) and single nucleotide polymorphism array (SNP-array) were performed to detect potential mutation in the patients.</p><p><b>RESULTS</b>No abnormal karyotype was detected in either patient. Deletions in 7q11.23 region (1.36 Mb and 1.73 Mb, respectively) were discovered by SNP-array for the two patients. In both patients, de novo heterozygous deletion of ELN and LIMK1 genes was confirmed by MLPA analysis.</p><p><b>CONCLUSION</b>The genotypes of the two patients were identified by molecular genetic analysis, which has facilitated interpretation of the phenotypes of these patient. According to the deletion mutation, prenatal diagnosis for the family could be performed in the future.</p>

LIM kinases and their roles in the nervous system / 浙江大学学报·医学版

LIM kinase-1 (LIMK1) and LIM kinase-2 (LIMK2) are kinases that have serine/threonine and tyrosine dual specificity. Although they show significant structural similarity, LIMK1 and LIMK2 have different expression patterns, subcellular localization, and functions. Activation of LIM kinases regulates the downstream of Rho GTPases, and influences the architecture of the actin cytoskeleton by regulating the activity of cofilin. Recent studies have shown that LIM kinases play important roles in the nervous system. For example, development of the central nervous system is reliant upon the presence of LIMK1, and deletion of Limk1 gene is involved in the development of the human genetic disorder Williams syndrome. Therefore, it is of vital physiological significance to investigate the neuronal function of LIM kinases. In this review, we outline the structure, phosphorylation regulation and neuronal function of LIM kinases, so as to provide new ideas for the treatment of these neurological diseases.

Effect of cytoskeleton reorganization inhibition on the activation of extracellular signal-regulated kinase in osteoblasts by fluid shear stress / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effect of cytoskeleton reorganization inhibition with RNA interference on the activation of extracellular signal-regulated kinase (ERK1/2) in primary osteoblasts induced by fluid shear stress (FSS).</p><p><b>METHODS</b>BALB/c mouse primary cultured osteoblasts were isolated by enzyme digestion technique. Osteoblasts were treated with LIM domain kinase 2 (LIM-2) specific siRNA or negative control siRNA, and then were loaded or unloaded by FSS of 1.2 Pa for 0, 5, 15, 30 and 60 min, respectively. The Western blotting was performed to detect the protein expression levels of P-ERK1/2 and ERK1/2, respectively. Two-way ANOVA and one-way ANOVA were used in data analysis.</p><p><b>RESULTS</b>FSS loading for different time (0, 5, 15, 30, 60 min) treated with negative RNA inteference had significant effect on the levels of P-ERK/ERK ratio (0.047 ± 0.031, 0.253 ± 0.137, 0.390 ± 0.155, 0.613 ± 0.123, 0.680 ± 0.108, respectively, P < 0.01). Statistical analysis showed that there was significant interaction between FSS and cytoskeleton reorganization inhibition treated with RNA inteference on the levels of P-ERK/ERK ratio (P < 0.01). The levels of P-ERK/ERK ratio increased when osteoblasts were loaded for 5 - 15 min (0.623 ± 0.129 and 0.623 ± 0.064, respectively, P < 0.05) and returned to baseline at 30 min (0.333 ± 0.086), and then reached the peak at 60 min (0.667 ± 0.064, P < 0.01).</p><p><b>CONCLUSIONS</b>FSS could activate ERK1/2 rapidly in primary cultured osteoblasts. Cytoskeleton reorganization inhibition treated with RNA interference speeded-up the activation of ERK1/2 by FSS, which could increase the sensitivity of ERK1/2 to FSS.</p>