Microsatellite DNA and RAPD fingerprinting,identification and genetic relationships of hybrid poplar (<Emphasis Type="Italic">Populus x canadensis</Emphasis>) cultivars

Microsatellite DNA markers of ten SSR loci and 248 RAPD loci (resolved by 26 RAPD primers) were used for DNA fingerprinting and differentiation of 17 widely grown Populus x canadensis syn. Populus x euramericana (interspecific Populus deltoides x Populus nigra hybrids) cultivars ("Baden 431", "Blanc du Poitou", "Canada Blanc", "Dorskamp 925", "Eugenei", "Gelrica", "Grandis", "Heidemij", "I-55/56", "I-132/56", "I-214", "Jacometti", "Ostia", "Regenerata", "Robusta", "Steckby" and "Zurich 03/3"), and determination of their genetic interrelationships. Informativeness of microsatellite and RAPD markers was also evaluated in comparison with allozyme markers for clone/cultivar identification in P. x canadensis. High microsatellite DNA and RAPD genetic diversity was observed in the sampled cultivars. All of the 17 P. x canadensis cultivars could be differentiated by their multilocus genotypes at four SSR loci, and were heterozygous for their parental species-specific alleles at the PTR6 SSR locus. Except for "Canada Blanc" and "Ostia", which had identical RAPD patterns, all cultivars could also be differentiated by RAPD fingerprints produced by each of the two RAPD primers, OPA07 and OPB15. For microsatellites, the mean number of alleles, polymorphic information content, observed heterozygosity, observed number of genotypes and the number of cultivars with unique genotypes per locus was 5.2, 0.64, 0.67, 5.7 and 2.2, respectively. For RAPD markers, the number of haplotypes per locus, and the number of cultivars with unique RAPD profiles per locus were 1.06 and 0.72, respectively. Overall, microsatellite DNA markers were the most informative for DNA fingerprinting of P. x canadensis cultivars. On the per locus basis, microsatellites were about six-times more informative than RAPD markers and about nine-times more informative than allozyme markers. However, on the per primer basis, RAPD markers were more informative. The UPGMA cluster plots separated the 17 cultivars into two major groups based on their microsatellite genotypic similarities, and into three major groups based on their RAPD fragment similarities. Both the microsatellite and RAPD data suggest that the cultivars "Baden 431", "Heidemij", "Robusta" and "Steckby" are genetically closely related. The inter-cultivar genetic relationships from microsatellite DNA and RAPD markers were consistent with those observed from allozyme markers, and were in general agreement with their speculated origin. Microsatellite DNA and RAPD markers could be used for clone and cultivar identification, varietal control and registration, and stock handling in P. x canadensis.     

Activation of Notch Signaling Is Required for Cholangiocarcinoma Progression and Is Enhanced by Inactivation of p53 In Vivo

Cholangiocacinoma (CC) is a cancer disease with rising incidence. Notch signaling has been shown to be deregulated in many cancers. However, the role of this signaling pathway in the carcinogenesis of CC is still not fully explored. In this study, we investigated the effects of Notch inhibition by γ-secretase inhibitor IX (GSI IX) in cultured human CC cell lines and we established a transgenic mouse model with liver specific expression of the intracellular domain of Notch (Notch-ICD) and inactivation of tumor suppressor p53. GSI IX treatment effectively impaired cell proliferation, migration, invasion, epithelial to mesenchymal transition and growth of softagar colonies. In vivo overexpression of Notch-ICD together with an inactivation of p53 significantly increased tumor burden and showed CC characteristics. Conclusion: Our study highlights the importance of Notch signaling in the tumorigenesis of CC and demonstrates that additional inactivation of p53 in vivo.     

Common Oncogenic Mutations Are Infrequent in Oral Squamous Cell Carcinoma of Asian Origin

Objectives

The frequency of common oncogenic mutations and TP53 was determined in Asian oral squamous cell carcinoma (OSCC).

Materials and Methods

The OncoCarta^™ panel v1.0 assay was used to characterize oncogenic mutations. In addition, exons 4-11 of the TP53 gene were sequenced. Statistical analyses were conducted to identify associations between mutations and selected clinico-pathological characteristics and risk habits.

Results

Oncogenic mutations were detected in PIK3CA (5.7%) and HRAS (2.4%). Mutations in TP53 were observed in 27.7% (31/112) of the OSCC specimens. Oncogenic mutations were found more frequently in non-smokers (p = 0.049) and TP53 truncating mutations were more common in patients with no risk habits (p = 0.019). Patients with mutations had worse overall survival compared to those with absence of mutations; and patients who harbored DNA binding domain (DBD) and L2/L3/LSH mutations showed a worse survival probability compared to those patients with wild type TP53. The majority of the oncogenic and TP53 mutations were G:C > A:T and A:T > G:C base transitions, regardless of the different risk habits.

Conclusion

Hotspot oncogenic mutations which are frequently present in common solid tumors are exceedingly rare in OSCC. Despite differences in risk habit exposure, the mutation frequency of PIK3CA and HRAS in Asian OSCC were similar to that reported in OSCC among Caucasians, whereas TP53 mutations rates were significantly lower. The lack of actionable hotspot mutations argue strongly for the need to comprehensively characterize gene mutations associated with OSCC for the development of new diagnostic and therapeutic tools.     

RNF185 Is a Novel E3 Ligase of Endoplasmic Reticulum-associated Degradation (ERAD) That Targets Cystic Fibrosis Transmembrane Conductance Regulator (CFTR)

In the endoplasmic reticulum (ER), misfolded or improperly assembled proteins are exported to the cytoplasm and degraded by the ubiquitin-proteasome pathway through a process called ER-associated degradation (ERAD). ER-associated E3 ligases, which coordinate substrate recognition, export, and proteasome targeting, are key components of ERAD. Cystic fibrosis transmembrane conductance regulator (CFTR) is one ERAD substrate targeted to co-translational degradation by the E3 ligase RNF5/RMA1. RNF185 is a RING domain-containing polypeptide homologous to RNF5. We show that RNF185 controls the stability of CFTR and of the CFTRΔF508 mutant in a RING- and proteasome-dependent manner but does not control that of other classical ERAD model substrates. Reciprocally, its silencing stabilizes CFTR proteins. Turnover analyses indicate that, as RNF5, RNF185 targets CFTR to co-translational degradation. Importantly, however, simultaneous depletion of RNF5 and RNF185 profoundly blocks CFTRΔF508 degradation not only during translation but also after synthesis is complete. Our data thus identify RNF185 and RNF5 as a novel E3 ligase module that is central to the control of CFTR degradation.     

Stress-protective and cross action of the extracellular reactivating factor of the microorganisms of the domains Bacteria, Archaea, and Eukaryota

Cross protection of members of the domains Bacteria, Archaea, and lower Eukaryota from stress factors due to the action of extracellular low-molecular metabolites with adaptogenic functions was shown. The adaptogen produced by Luteococcus japonicus subsp. casei and described previously as a reactivating factor (RF) was shown to protect the yeasts Saccharomyces cerevisiae, archaea Haloarcula marismorti, and the cells of higher eukaryotes (HeLa) against weak stressor impacts. Production of an archaeal extracellular metabolite with a weak adaptogenic effect of the producer cells and capable of a threefold increase in survival of heat-inactivated yeast cells was discovered. Our results confirm the similarity of the compensatory adaptive reactions in prokaryotes (bacteria and archaea) and eukaryotes.     

Condition‐dependent expression of pre‐ and postcopulatory sexual traits in guppies

Female choice can impose persistent directional selection on male sexually selected traits, yet such traits often exhibit high levels of phenotypic variation. One explanation for this paradox is that if sexually selected traits are costly, only the fittest males are able to acquire and allocate the resources required for their expression. Furthermore, because male condition is dependent on resource allocation, condition dependence in sexual traits is expected to underlie trade‐offs between reproduction and other life‐history functions. In this study we test these ideas by experimentally manipulating diet quality (carotenoid levels) and quantity in the guppy (Poecilia reticulata), a livebearing freshwater fish that is an important model for understanding relationships between pre‐ and post‐copulatory sexually selected traits. Specifically, we test for condition dependence in the expression of pre‐ and postcopulatory sexual traits (behavior, ornamentation, sperm traits) and determine whether diet manipulation mediates relationships among these traits. Consistent with prior work we found a significant effect of diet quantity on the expression of both pre‐ and postcopulatory male traits; diet‐restricted males performed fewer sexual behaviors and exhibited significant reductions in color ornamentation, sperm quality, sperm number, and sperm length than those fed ad libitum. However, contrary to our expectations, we found no significant effect of carotenoid manipulation on the expression of any of these traits, and no evidence for a trade‐off in resource allocation between pre‐ and postcopulatory episodes of sexual selection. Our results further underscore the sensitivity of behavioral, ornamental, and ejaculate traits to dietary stress, and highlight the important role of condition dependence in maintaining the high variability in male sexual traits.     

Plasma proteome analysis of cervical intraepithelial neoplasia and cervical squamous cell carcinoma

Although cervical cancer is preventable with early detection, it remains the second most common malignancy among women. An understanding of how proteins change in their expression during a particular diseased state such as cervical cancer will contribute to an understanding of how the disease develops and progresses. Potentially, it may also lead to the ability to predict the occurrence of the disease. With this in mind, we aimed to identify differentially expressed proteins in the plasma of cervical cancer patients. Plasma from control, cervical intraepithelial neoplasia (CIN) grade 3 and squamous cell carcinoma (SCC) stage IV subjects was resolved by two-dimensional gel electrophoresis and the resulting proteome profiles compared. Differentially expressed protein spots were then identified by mass spectrometry. Eighteen proteins were found to be differentially expressed in the plasma of CIN 3 and SCC stage IV samples when compared with that of controls. Competitive ELISA further validated the expression of cytokeratin 19 and tetranectin. Functional analyses of these differentially expressed proteins will provide further insight into their potential role(s) in cervical cancer-specific monitoring and therapeutics.     

Allograft Tissue for Use in Valve Replacement

Homograft or allograft tissue has been available for use as replacement for diseased valves or reconstruction of major vessels for decades. However, with respect to replacement of diseased valvular tissue the search for the ideal valve still continues. In this review we will discuss the clinical indications, surgical techniques, and outcome of aortic homografts.