Medical sequencing of candidate genes for nonsyndromic cleft lip and palate

Nonsyndromic or isolated cleft lip with or without cleft palate (CL/P) occurs in wide geographic distribution with an average birth prevalence of 1/700. We used direct sequencing as an approach to study candidate genes for CL/P. We report here the results of sequencing on 20 candidate genes for clefts in 184 cases with CL/P selected with an emphasis on severity and positive family history. Genes were selected based on expression patterns, animal models, and/or role in known human clefting syndromes. For seven genes with identified coding mutations that are potentially etiologic, we performed linkage disequilibrium studies as well in 501 family triads (affected child/mother/father). The recently reported MSX1 P147Q mutation was also studied in an additional 1,098 cleft cases. Selected missense mutations were screened in 1,064 controls from unrelated individuals on the Centre d'Étude du Polymorphisme Humain (CEPH) diversity cell line panel. Our aggregate data suggest that point mutations in these candidate genes are likely to contribute to 6% of isolated clefts, particularly those with more severe phenotypes (bilateral cleft of the lip with cleft palate). Additional cases, possibly due to microdeletions or isodisomy, were also detected and may contribute to clefts as well. Sequence analysis alone suggests that point mutations in FOXE1, GLI2, JAG2, LHX8, MSX1, MSX2, SATB2, SKI, SPRY2, and TBX10 may be rare causes of isolated cleft lip with or without cleft palate, and the linkage disequilibrium data support a larger, as yet unspecified, role for variants in or near MSX2, JAG2, and SKI. This study also illustrates the need to test large numbers of controls to distinguish rare polymorphic variants and prioritize functional studies for rare point mutations.     

Maternal vitamin B-6 and folate status and risk of oral cleft birth defects in the Philippines

BACKGROUND: Vitamin deficiencies induce oral clefts in animal experiments, but the role of specific nutrients in human oral clefts is uncertain. METHODS: Associations between maternal vitamin B-6 and folate status and risk of nonsyndromic cleft lip, with or without cleft palate (CL/P), were examined in case-control studies at two sites in the Philippines--Negros Occidental and Davao. Cases were mothers of affected children and control mothers were those who had no children with oral clefts. RESULTS: The risk of having a CL/P-affected child increased with increasing tertile of vitamin B-6 deficiency in both Negros Occidental and Davao (odds ratios [ORs] and 95% confidence intervals [CIs] for sites combined = 1.0 [reference], OR, 2.94; 95% CI, 1.51-5.73; OR, 4.98; 95% CI, 2.56-9.67). Poor B-6 status had a stronger association with CL/P among mothers with lower versus higher plasma folate levels. Increasing tertiles of plasma folate were marginally associated with an increased risk of clefts in both sites combined (1.0 [reference]; OR, 1.58; 95% CI, 0.93-2.68; OR, 1.59; 95% CI, 0.94-2.70). Increasing tertiles of erythrocyte folate were associated with a decreased risk of CL/P in Negros Occidental (1.0 [reference]; OR, 0.34; 95% CI, 0.13-0.90; OR, 0.46; 95% CI, 0.20-1.09) and an increased risk in Davao (1.0 [reference]; OR, 1.23; 95% CI, 0.54-2.81; OR, 4.85; 95% CI, 2.24-10.50). The inconsistent associations between folate status and CL/P risk appeared to be a result of statistical interaction between folate, vitamin B-6, and case-control status that produced different results in study areas of higher versus lower prevalence of vitamin B-6 deficiency. CONCLUSIONS: Poor maternal vitamin B-6 status was consistently associated with an increased risk of CL/P at two sites in the Philippines. Folate-CL/P associations were inconsistent and may be related to the vitamin B-6 status or other characteristics of the populations under study.     

The effect of progesterone replacement on gene expression in the corpus luteum during induced regression and late luteal phase in the bonnet monkey (<Emphasis Type="Italic">Macaca radiata</Emphasis>)

Background  

In higher primates, although LH/CG play a critical role in the control of corpus luteum (CL) function, the direct effects of progesterone (P4) in the maintenance of CL structure and function are unclear. Several experiments were conducted in the bonnet monkey to examine direct effects of P4 on gene expression changes in the CL, during induced luteolysis and the late luteal phase of natural cycles.     

Down-regulation of the M6P/IGF-II receptor increases cell proliferation and reduces apoptosis in neonatal rat cardiac myocytes

Background  

The mannose 6-phosphate/insulin-like growth factor-II receptor (M6P/IGF2R) is a multi-functional protein that has been implicated in regulation of cell growth and apoptosis. Cardiac myocytes express relatively high levels of M6P/IGF2R, and cardiomyocyte apoptosis has been identified in a variety of cardiovascular disorders, such as myocardial infarction and heart failure. However, involvement of M6P/IGF2R in the pathogenesis of these conditions has not been determined. Thus, the objective of this study was to determine the role of M6P/IGF2R in regulation of cardiac myocyte growth and apoptosis.     

Downregulation of long non-coding RNA H19 promotes P19CL6 cells proliferation and inhibits apoptosis during late-stage cardiac differentiation via miR-19b-modulated Sox6

Background

Regulating cardiac differentiation to maintain normal heart development and function is very important. At present, biological functions of H19 in cardiac differentiation is not completely clear.

Methods

To explore the functional effect of H19 during cardiac differentiation. Expression levels of early cardiac-specific markers Nkx-2.5 and GATA4, cardiac contractile protein genes α-MHC and MLC-2v were determined by qRT-PCR and western lot. The levels of lncRNA H19 and miR-19b were detected by qRT-PCR. We further predicted the binding sequence of H19 and miR-19b by online softwares starBase v2.0 and TargetScan. The biological functions of H19 and Sox6 were evaluated by CCK-8 kit, cell cycle and apoptosis assay and caspase-3 activity.

Results

The expression levels of α-MHC, MLC-2v and H19 were upregulated, and miR-19b was downregulated significantly in mouse P19CL6 cells at the late stage of cardiac differentiation. Biological function analysis showed that knockdown of H19 promoted cell proliferation and inhibits cell apoptosis. H19 suppressed miR-19b expression and miR-19b targeted Sox6, which inhibited cell proliferation and promoted apoptosis in P19CL6 cells during late-stage cardiac differentiation. Importantly, Sox6 overexpression could reverse the positive effects of H19 knockdown on P19CL6 cells.

Conclusion

Downregulation of H19 promoted cell proliferation and inhibited cell apoptosis during late-stage cardiac differentiation by regulating the negative role of miR-19b in Sox6 expression, which suggested that the manipulation of H19 expression could serve as a potential strategy for heart disease.

     

A three-phase <Emphasis Type="Italic">in-vitro</Emphasis> system for studying <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis> adhesion and biofilm formation upon hydrogel contact lenses

Background  

Pseudomonas aeruginosa is commonly associated with contact lens (CL) -related eye infections, for which bacterial adhesion and biofilm formation upon hydrogel CLs is a specific risk factor. Whilst P. aeruginosa has been widely used as a model organism for initial biofilm formation on CLs, in-vitro models that closely reproduce in-vivo conditions have rarely been presented.     

Preservation of protein clefts in comparative models

Background  

Comparative, or homology, modelling of protein structures is the most widely used prediction method when the target protein has homologues of known structure. Given that the quality of a model may vary greatly, several studies have been devoted to identifying the factors that influence modelling results. These studies usually consider the protein as a whole, and only a few provide a separate discussion of the behaviour of biologically relevant features of the protein. Given the value of the latter for many applications, here we extended previous work by analysing the preservation of native protein clefts in homology models. We chose to examine clefts because of their role in protein function/structure, as they are usually the locus of protein-protein interactions, host the enzymes' active site, or, in the case of protein domains, can also be the locus of domain-domain interactions that lead to the structure of the whole protein.     

Insulin induces proliferation and cardiac differentiation of P19CL6 cells in a dose‐dependent manner

Insulin is a peptide hormone produced by beta cells of the pancreas. The roles of insulin in energy metabolism have been well studied, with most of the attention focused on glucose utilization, but the roles of insulin in cell proliferation and differentiation remain unclear. In this study, we observed for the first time that 10 nmol/L insulin treatment induces cell proliferation and cardiac differentiation of P19CL6 cells, whereas 50 and 100 nmol/L insulin treatment induces P19CL6 cell apoptosis and blocks cardiac differentiation of P19CL6 cells. By using real‐time polymerase chain reaction (PCR) and Western blotting analysis, we found that the mRNA levels of cyclin D1 and α myosin heavy chain (α‐MHC) are induced upon 10 nmol/L insulin stimulation and inhibited upon 50/100 nmol/L insulin treatment, whereas the mRNA levels of BCL‐2‐antagonist of cell death (BAD) exists a reverse trend. The similar results were observed in P19CL6 cells expressing GATA‐6 or peroxisome proliferator‐activated receptor α (PPARα). Our results identified the downstream targets of insulin, cyclin D1, BAD, α‐MHC, and GATA‐4, elucidate a novel molecular mechanism of insulin in promoting cell proliferation and differentiation.