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Here we have reported novel polymeric devices to control fluid flow using surface forces and capillary action to facilitate counter-diffusive, on-chip protein crystallization.

Heat shock protein 70 (Hsp70) chaperones bind many different sequences and discriminate between incompletely folded and folded clients. Most research into the origins of this "selective promiscuity" has relied on short peptides as substrates to dissect the binding, but much less is known about how Hsp70s bind full-length client proteins. Here, we connect detailed structural analyses of complexes between the Escherichia coli Hsp70 (DnaK) substrate-binding domain (SBD) and peptides encompassing five potential binding sites in the precursor to E. coli alkaline phosphatase (proPhoA) with SBD binding to full-length unfolded proPhoA. Analysis of SBD complexes with proPhoA peptides by a combination of X-ray crystallography, methyl-transverse relaxation optimized spectroscopy (methyl-TROSY), and paramagnetic relaxation enhancement (PRE) NMR and chemical cross-linking experiments provided detailed descriptions of their binding modes. Importantly, many sequences populate multiple SBD binding modes, including both the canonical N to C orientation and a C to N orientation. The favored peptide binding mode optimizes substrate residue side-chain compatibility with the SBD binding pockets independent of backbone orientation. Relating these results to the binding of the SBD to full-length proPhoA, we observe that multiple chaperones may bind to the protein substrate, and the binding sites, well separated in the proPhoA sequence, behave independently. The hierarchy of chaperone binding to sites on the protein was generally consistent with the apparent binding affinities observed for the peptides corresponding to these sites. Functionally, these results reveal that Hsp70s "read" sequences without regard to the backbone direction and that both binding orientations must be considered in current predictive algorithms.

Ca2+/calmodulin dependent protein kinase II (CaMKII) is a signaling protein that is required for successful long-term memory formation. Ca2+/CaM activates CaMKII by binding to its regulatory segment, thereby making the substrate binding pocket available. One exceptional feature of this kinase is that two binding partners have been shown persistently activate CaMKII after the Ca2+ stimulus dissipates. The molecular details of this phenomenon are unclear. Despite having a large variety of interaction partners, the specificity of CaMKII has not been structurally well-characterized. To this end, we solved X-ray crystal structures of the CaMKII kinase domain bound to four different binding partners: a peptide substrate, a substrate/activator, a substrate/binding partner, and an inhibitor (AMPA-type glutamate receptor, NMDA-type glutamate receptor, Tiam1, and Densin-180). We show that all four binding partners use similar interactions to bind across the substrate binding pocket of the CaMKII active site. We generated a sequence alignment based on our structural observations, which revealed conserved interactions across these binding partners. The structures presented here shed much-needed light on the interaction between CaMKII and its binding partners. These observations will be crucial in guiding further biological experiments.

Bu araştırmada üniversite öğrencilerinin karar vermede özsaygı ve karar verme stillerinin akılcı olmayan inançlar ve cinsiyet açısından anlamlı düzeyde farklılaşıp farklılaşmadığı ve akılcı olmayan inançlar ile karar verme stilleri arasındaki ilişki incelenmiştir. Araştırmanın genel evrenini, Selçuk Üniversitesi' nin farklı fakültelerinde öğrenim görmekte olan 1.,2.,3. ve 4. sınıf öğrencileri oluşturmaktadır. Araştırmanın çalışma evreni Eğitim Fakültesi, Mesleki Eğitim Fakültesi, Fen Edebiyat Fakültesi ve Teknik Eğitim Fakültesi olarak belirlenmiştir. Araştırma örneklemi bu fakültelerin çeşitli bölümlerinde öğrenim görmekte olan öğrencilerden tesadüfi küme örnekleme yöntemi ile seçilmiştir. Araştırma örneklemi toplam 750 öğrenciden oluşmaktadır. Araştırmada; Türküm (2003) tarafından geliştirilen Akılcı Olmayan İnanç Ölçeği, Deniz (2004) tarafından Türkçeye uyarlanan Melbourne Karar Verme Ölçeği kullanılmıştır. Verilerin analizinde t testi ve Pearson momentler çarpımı korelasyonu kullanılmıştır. Tüm veriler 0.05 anlamlılık düzeyinde test edilmiştir. Araştırmadan elde edilen bulgular kısaca şöyle özetlenebilir: - Araştırma bulguları karar vermede özsaygı, dikkatli, kaçıngan ve erteleyici karar verme stili düzeylerinin cinsiyete göre farklılaşmadığı ancak öğrencilerin panik karar verme stili düzeyleri arasında cinsiyete göre anlamlı bir farklılık olduğunu göstermektedir. Araştırma bulgusuna göre, kız öğrencilerin panik karar verme düzeyleri erkek öğrencilere göre daha yüksek bulunmuştur. - Akılcı olmayan inançlar ile özsaygı karar verme stili arasında negatif yönde, dikkatli, kaçıngan, erteleyici ve panik karar verme stili arasında da pozitif yönde anlamlı ilişki bulunmuştur. - Akılcı olmayan inanç ölçeği puanları ortalamanın altında yani akılcı olmayan inanç ölçeği puanları düşük olan öğrencilerin karar verme ölçeği erteleyici, panik ve kaçıngan alt boyutlarında negatif yönde anlamlı bir ilişki; özsaygı alt boyutunda pozitif yönde anlamlı bir ilişki olduğu bulunmuş, dikkatli alt boyutunda anlamlı bir ilişki bulunmamıştır., In this study,university students? self-esteem in decision making and decision making styles have been searched in order to see whether there is a significant differentiation among them according to irrational beliefs and sex, and also the relation between irrational beliefs and decision making styles have been searched. The general scope of study is the students of Selcuk University who are in 1st , 2nd, 3rd and 4th grades. The labor scope of study contains the students from Faculty of Education, Faculty of Vocational Education, Faculty of Science and Literature and Faculty of Technical Education. The sample of study was chosen from these mentioned faculties? students by using random sampling method. The study sample contains 750 students. In this research, Irrational Belief Scale developed by Türküm (2003), Melbourne Decision Making Scale translated into Turkish by Deniz (2004) was used. t-Test and Pearson Product-Moment Correlation Coefficients are used to analyze data. The significance levels is determined to be 0.05. The findings of the study can be summarized as following; - The study shows that self-esteem, vigilance, buckpassing and procrastinating styles in decision making are not differentiated in accordance with students? sex; however students? hypervigilance style level in decision making shows a significant difference in accordance with their sex. According to data, it has been found that female students? hypervigilance decision making styles are higher than male students?. - The negative significant relation has been found between irrational beliefs and self-esteem in decision making; however, positive significant relation has been found between irrational beliefs and vigilance, buckpassing, procrastinating and hypervigilance in decision making style. - The negative significant relation has been found between the sub-scales of procrastinating, hypervigilance and buckpassing in decision making and irrational belief scale points of students?, having lower point from average; the positive significant relation has been found between the same students? irrational belief scale points and sub-scale of self-esteem in decision making, at the same time any significant relation in sub-scale of vigilance can not be found.