Casein Kinase II: An attractive target for anti-cancer drug design

Casein Kinase II (CK2) is a ubiquitous serine/threonine kinase that is highly conserved in eukaryotic cells. CK2 has been shown to impact cell growth and proliferation, as numerous growth-related proteins are substrates of CK2. More importantly, experimental evidence linking increased expression and activity of CK2 to human cancers underscores the relevance of CK2 biology to cellular transformation and carcinogenesis. Due to the critical regulatory role CK2 plays in cell fate determination in cancer cells, there is a tremendous interest in the development of CK2-specific therapies. Supporting this, recent reports have demonstrated that genetic manipulation of CK2 expression as well as pharmacological inhibition of its enzymatic activity sensitizes cancers to apoptotic stimuli. Here we provide a succinct account of the biology of CK2, its cellular substrates, its pro-survival and pro-proliferation activity, and highlight evidence for its involvement in human cancer.     

Thermodynamic Characterization of the Interaction between Prefoldin and Group II Chaperonin

Prefoldin (PFD) is a hexameric chaperone that captures a protein substrate and transfers it to a group II chaperonin (CPN) to complete protein folding. We have studied the interaction between PFD and CPN using those from a hyperthermophilic archaeon, Thermococcus strain KS-1 (T. KS-1). In this study, we determined the crystal structure of the T. KS-1 PFDβ2 subunit and characterized the interactions between T. KS-1 CPNs (CPNα and CPNβ) and T. KS-1 PFDs (PFDα1-β1 and PFDα2-β2). As predicted from its amino acid sequence, the PFDβ2 subunit conforms to a structure similar to those of the PFDβ1 subunit and the Pyrococcus horikoshii OT3 PFDβ subunit, with the exception of the tip of its coiled-coil domain, which is thought to be the CPN interaction site. The interactions between T. KS-1 CPNs and PFDs (CPNα and PFDα1-β1; CPNα and PFDα2-β2; CPNβ and PFDα1-β1; and CPNβ and PFDα2-β2) were analyzed using the Biacore T100 system at various temperatures ranging from 20 to 45 ºC. The affinities between PFDs and CPNs increased with an increase in temperature. The thermodynamic parameters calculated from association constants showed that the interaction between PFD and CPN is entropy driven. Among the four combinations of PFD-CPN interactions, the entropy difference in binding between CPNβ and PFDα2-β2 was the largest, and affinity significantly increased at higher temperatures. Considering that expression of PFDα2-β2 and CPNβ subunit is induced upon heat shock, our results suggest that PFDα1-β1 is a general PFD for T. KS-1 CPNs, whereas PFDα2-β2 is specific for CPNβ.     

Land Use Changes Assessment using a triangulated framework: Perception Interviews,Land-Use/Land Cover Observation,and Spatial Planning Analysis in Tanjung Batu and Derawan Island,Indonesia

Human Ecology - Understanding land-use change is imperative in the management of Indonesian coastal ecosystems with numerous environmental impacts generated from land-use conversion. To assess...     

SYBR Green I and TaqMan quantitative real-time polymerase chain reaction methods for the determination of amplification of Plasmodium falciparum multidrug resistance-1 gene (pfmdr1)

The pfmdr1 gene, which encodes P-glycoprotein homolog 1, has been shown to be a reliable marker of resistance for Plasmodium falciparum related to artesunate and mefloquine combination therapy. The aims of this study are to investigate the copy number of pfmdr1 in P. falciparum isolates collected from the 4 malaria-endemic areas of Thailand (Kanchanaburi, Mae Hongson, Ranong, and Tak) along the Thailand-Myanmar (Burma) border (Thai-Myanmar border) by using SYBR Green I and the standard method TaqMan real-time polymerase chain reaction (RT-PCR) and to compare the efficiency (sensitivity and specificity) of SYBR Green I with TaqMan RT-quantitative (q)PCR methods in determining pfmdr1 gene copy number. Ninety-six blood samples were collected onto filter paper from patients with uncomplicated falciparum malaria who attended malaria clinics in the Kanchanaburi (n = 45), Mae Hongson (n = 18), Ranong (n = 11), and Tak (n = 22) provinces in Thailand. Parasite genomic DNA was extracted from dried blood spots by using QIAcube? automated sample preparation. Pfmdr1 gene copy number was determined by TaqMan (63 samples) and SYBR Green I (96 samples) real-time PCR. Seventy-one (74.0%), 14 (14.6%), 10 (10.4%), and 1 (1%) isolates carried 1, 2, 3, and 4 pfmdr1 gene copies, respectively. Forty-three of 48 (89.6%), 6 of 11 (54.5%), and 3 of 4 (75.0%) samples, respectively, showed agreement with results of 1, 2, and 3 pfmdr1 gene copies as determined by both methods. The efficiency of SYBR Green I in identifying pfmdr1 gene copy number was found to be significantly correlated with that of TaqMan. Considering its simplicity and relatively low cost, SYBR Green I RT-qPCR is therefore a promising alternative technique for the determination of pfmdr1 copy number.     

The small GTPase BcCdc42 affects nuclear division, germination and virulence of the gray mold fungus Botrytis cinerea

The small GTPase Cdc42 plays a central role in various processes in eukaryotic cells including growth, differentiation and cytoskeleton organization. Whereas it is essential in the yeast Saccharomyces cerevisiae, its role in filamentous fungi differs, due to the complementing, partly overlapping function of Rac. We analyzed the role of the Cdc42 homologue in the necrotrophic, broad host range pathogen Botrytis cinerea. Deletion mutants of bccdc42 showed various growth abnormalities; the mutants had reduced growth rate and hyphal branching, they produced fewer conidia, which were enlarged and misshapen and had germination defects. Additionally, the mutants were impaired in sclerotia development. Cytological studies indicate that at least part of this phenotype could be attributed to disturbed control of nuclear division: conidia and hyphae of the mutant showed twofold higher nucleus/cytoplasm ratio compared to wild type cells. Apart from these effects on vegetative growth and differentiation, Δbccdc42 strains were attenuated in penetration and colonization of host tissue, confirming that BcCdc42 – though being not essential like in yeast – is involved in important developmental processes in B. cinerea.     

Smoking interacts with HLA-DRB1 shared epitope in the development of anti-citrullinated protein antibody-positive rheumatoid arthritis: results from the Malaysian Epidemiological Investigation of Rheumatoid Arthritis (MyEIRA)

Introduction

Rheumatoid arthritis (RA) is a multifactorial autoimmune disease in which genetic and environmental factors interact in the etiology. In this study, we investigated whether smoking and HLA-DRB1 shared-epitope (SE) alleles interact differently in the development of the two major subgroups of rheumatoid arthritis (RA), anti-citrullinated proteins antibody (ACPA)-positive and ACPA-negative disease, in a multiethnic population of Asian descent.

Methods

A case-control study comprising early diagnosed RA cases was carried out in Malaysia between 2005 and 2009. In total, 1,076 cases and 1,612 matched controls participated in the study. High-resolution HLA-DRB1 genotyping was performed for shared-epitope (SE) alleles. All participants answered a questionnaire on a broad range of issues, including smoking habits. The odds ratio (OR) of developing ACPA-positive and ACPA-negative disease was calculated for smoking and the presence of any SE alleles separately. Potential interaction between smoking history (defined as "ever" and "never" smoking) and HLA-DRB1 SE alleles also was calculated.

Results

In our multiethnic study, both the SE alleles and smoking were associated with an increased risk of developing ACPA-positive RA (OR SE alleles, 4.7; 95% confidence interval (CI), 3.6 to 6.2; OR smoking, 4.1; 95% CI, 1.9 to 9.2). SE-positive smokers had an odds ratio of ACPA-positive RA of 25.6 (95% CI, 10.4 to 63.4), compared with SE-negative never-smokers. The interaction between smoking and SE alleles was significant (attributable proportion due to interaction (AP) was 0.7 (95% CI, 0.5 to 1.0)). The HLA-DRB1*04:05 SE allele, which is common in Asian populations, but not among Caucasians, was associated with an increased risk of ACPA-positive RA, and this allele also showed signs of interaction with smoking (AP, 0.4; 95% CI, -0.1 to 0.9). Neither smoking nor SE alleles nor their combination was associated with an increased risk of ACPA-negative RA.

Conclusions

The risk of developing ACPA-positive RA is associated with a strong gene-environment interaction between smoking and HLA-DRB1 SE alleles in a Malaysian multiethnic population of Asian descent. This interaction seems to apply also between smoking and the specific HLA-DRB1*04:05 SE allele, which is common in Asian populations but not in Caucasians.     

Biodegradation of 2-Chlorobenzoic Acid by Enterobacter cloacae: Growth Kinetics and Effect of Growth Conditions

Enterobacter cloacae was originally isolated from soil irrigated with wastewater on the basis of its ability to grow with linear alkylbenzene sulfonate (LAS) as the sole source for carbon and energy. The isolated bacterium was grown in batch cultures using a 2-chlorobenzoic acid (2-CBA)-containing minimal salt medium (MSM). 2-CBA was found to be the sole source for carbon and energy. 2-CBA inhibited the growth rate with a maximum concentration of 10 mM, after which no growth occurred. The Haldane model was used to predict the specific growth rate concentration data. 2-CBA degradation by starved E. cloaca cells was faster than that of nonstarved cells. The maximum growth rates on 2-CBA (2 mM) for starved and nonstarved cells reached only 0.34 and 0.28 h^?1, respectively. Glucose, lactose, sucrose, maltose, succinic acid, and mannitol as additional carbon sources at a fixed concentration (0.2%) caused the degradation rate of 2-CBA to proceed faster at ranges between 1.08- and 1.5-fold higher than that of the control. In contrast, using only fructose and sorbitol as the carbon sources showed catabolic repression of the degradation activity of 2-CBA by E. cloaca cells, although their cell mass was improved. All nitrogen sources supplied caused an increase in cell mass, whereas only lysine, alanine, glutamine, casein, and yeast extract caused a decrease in the degradation rate of 2-CBA, with a range between 12% and 28%. The activity of C120 could be detected in a crude extract of E. cloacae cells, indicating that the chloroaromatic ring fission occurs through the ortho pathways, not through the meta pathways. The data showed that different initial cell (inocula) densities did not affect the induction time for 2-CBA degradation. However, doubling the initial cell densities reduced the time required for reaching the complete degradation. 2-CBA degradation was optimally achieved at a 37°C incubation temperature and a pH of 7.5.     

The effects of Pueraria mirifica extract,diadzein and genistein in testosterone-induced prostate hyperplasia in male Sprague Dawley rats

Molecular Biology Reports - Pueraria mirifica (PM) is a medicinal plant native to Thailand contained high amount of phytoestrogen and possesses anticancer activity. This study reports the effect of...     

Structure and development of free neuromasts in barramundi, Lates calcarifer (Block)

This study was conducted to clarify the development of free neuromasts with growth of the barramundi, Lates calcarifer. A pair of free neuromasts was observed behind the unpigmented eyes in newly hatched eleutheroembryos with a mean total length of 1.93 mm, and two-hour-old eleuthero-embryos could respond to an approaching pipette. At 2 days after hatching, the egg yolk sac was mostly consumed, the eyes were pigmented, and the larvae commenced feeding on rotifers. Free neuromasts increased in number with growth and commenced developing into canal neuromasts in barramundi 15 days old with a mean total length of 8.07 mm. The average length of the major axis of the trunk free neuromasts attained approximately 12.9-15.5 microm, and the number of sensory cells was 15.4-17.5 at 15-20 days old. Developed cupulae of free neuromasts were observed in 1-day-old eleutheroembryos. The direction of maximum sensitivity of free neuromasts, determined from the polarity of the sensory cells, coincided with the minor axis of the lozenge-shaped outline of the apical surface of the free neuromasts. The polarity of trunk neuromasts was usually oriented along the antero-posterior axis of the fish body, but a few had a dorso-ventral direction. On the head, free neuromasts were oriented on lines tangential to concentric circles around the eye.     

Diel changes in the CO2 exchange rates of reproductive organs of the tropical tree Durio zibethinus

The daily variations in the in situ CO₂ exchange of the reproductive organs of Durio zibethinus trees, growing in an experimental field at University Putra Malaysia (UPM), were examined at different growth stages. Reproductive organs emerged on the leafless portions of branches inside the crown. The photon flux densities (PFD) in the chambers used for the measurements were less than 100 mol m^–2 s^–1 and were 40% of the PFD outside of the crown. The daytime net respiration rate and the nighttime dark respiration rate were higher at the time of flower initiation and during the mixed stages, when flower buds, flowers, and fruit coexist, than at the flower bud stage. The net respiration rate was lower than the daytime dark respiration rate at given temperatures, especially at the flower bud and fruit stages. Conversely, the net respiration rate was similar to the daytime dark respiration rate at the mixed stage. Photosynthetic CO₂ refixation reduced the daily respiratory loss by 17, 5, 0.3, and 24% at the flower bud, flower initiation, mixed, and fruit stages, respectively.