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Full-Text Articles in Life Sciences

Structural Insights Into The Potency Of Sk Channel Positive Modulators, Young-Woo Nam, Razan Orfali, Tingting Liu, Kunqian Yu, Meng Cui, Heike Wulff, Miao Zhang Dec 2017

Structural Insights Into The Potency Of Sk Channel Positive Modulators, Young-Woo Nam, Razan Orfali, Tingting Liu, Kunqian Yu, Meng Cui, Heike Wulff, Miao Zhang

Pharmacy Faculty Articles and Research

Small-conductance Ca2+-activated K+ (SK) channels play essential roles in the regulation of cellular excitability and have been implicated in neurological and cardiovascular diseases through both animal model studies and human genetic association studies. Over the past two decades, positive modulators of SK channels such as NS309 and 1-EBIO have been developed. Our previous structural studies have identified the binding pocket of 1-EBIO and NS309 that is located at the interface between the channel and calmodulin. In this study, we took advantage of four compounds with potencies varying over three orders of magnitude, including 1-EBIO, NS309, SKS-11 (6-bromo-5-methyl-1H-indole-2,3-dione-3-oxime) and …


Combinational Sirna Delivery Using Hyaluronic Acid Modified Amphiphilic Polyplexes Against Cell Cycle And Phosphatase Proteins To Inhibit Growth And Migration Of Triple-Negative Breast Cancer Cells, Manoj B. Parmar, Daniel Nisakar Meenakshi Sundaram, Remant Bahadur Kc, Robert Maranchuk, Hamidreza Montazeri Aliabadi, Judith C. Hugh, Raimar Löbenberg, Hasan Uludağ Nov 2017

Combinational Sirna Delivery Using Hyaluronic Acid Modified Amphiphilic Polyplexes Against Cell Cycle And Phosphatase Proteins To Inhibit Growth And Migration Of Triple-Negative Breast Cancer Cells, Manoj B. Parmar, Daniel Nisakar Meenakshi Sundaram, Remant Bahadur Kc, Robert Maranchuk, Hamidreza Montazeri Aliabadi, Judith C. Hugh, Raimar Löbenberg, Hasan Uludağ

Pharmacy Faculty Articles and Research

Triple-negative breast cancer is an aggressive form of breast cancer with few therapeutic options if it recurs after adjuvant chemotherapy. RNA interference could be an alternative therapy for metastatic breast cancer, where small interfering RNA (siRNA) can silence the expression of aberrant genes critical for growth and migration of malignant cells. Here, we formulated a siRNA delivery system using lipid-substituted polyethylenimine (PEI) and hyaluronic acid (HA), and characterized the size, ζ-potential and cellular uptake of the nanoparticulate delivery system. Higher cellular uptake of siRNA by the tailored PEI/HA formulation suggested better interaction of complexes with breast cancer cells due to …


Cyclic Peptide Conjugate Of Curcumin And Doxorubicin As An Anticancer Agent, Shaban Darwish, Saghar Mozaffari, Keykavous Parang, Rakesh Tiwari Oct 2017

Cyclic Peptide Conjugate Of Curcumin And Doxorubicin As An Anticancer Agent, Shaban Darwish, Saghar Mozaffari, Keykavous Parang, Rakesh Tiwari

Pharmacy Faculty Articles and Research

The hydrophobicity of curcumin creates hurdle towards its use in the anticancer therapy. Herein, we synthesized a curcumin-doxorubicin conjugated cyclic peptide scaffold to improve the solubility of curcumin and create a conjugate containing two anticancer agents. A solid-phase Fmoc/tBu solid phase methodology was used to synthesize a cell-penetrating nuclear targeting peptide with free thiol and amine groups, which was coupled with the activated doxorubicin (Dox) and curcumin, affording Dox-peptide-curcumin conjugate (DPCC) (10). The antiproliferative activity of the conjugate was evaluated in human leukemia carcinoma cell (CCRF-CEM), human ovarian carcinoma cell (SKOV-3), and normal kidney cell line (LLCPK). Cyclic peptide-doxorubicin conjugate …


Translational Fidelity, Mistranslation, And The Cellular Responses To Stress, Kyle Mohler, Michael Ibba Aug 2017

Translational Fidelity, Mistranslation, And The Cellular Responses To Stress, Kyle Mohler, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Faithful translation of mRNA into the corresponding polypeptide is a complex multistep process, requiring accurate amino acid selection, transfer RNA (tRNA) charging and mRNA decoding on the ribosome. Key players in this process are aminoacyl-tRNA synthetases (aaRSs), which not only catalyse the attachment of cognate amino acids to their respective tRNAs, but also selectively hydrolyse incorrectly activated non-cognate amino acids and/or misaminoacylated tRNAs. This aaRS proofreading provides quality control checkpoints that exclude non-cognate amino acids during translation, and in so doing helps to prevent the formation of an aberrant proteome. However, despite the intrinsic need for high accuracy during translation, …


Carbonyl Reduction By Ymfi Completes The Modification Of Ef-P In Bacillus Subtilis To Prevent Accumulation Of An Inhibitory Modification State, Katherine R. Hummels, Anne Witzky, Andrei Rajkovic, Rodney Tollerson Ii, Lisa A. Jones, Michael Ibba, Daniel B. Kearns Aug 2017

Carbonyl Reduction By Ymfi Completes The Modification Of Ef-P In Bacillus Subtilis To Prevent Accumulation Of An Inhibitory Modification State, Katherine R. Hummels, Anne Witzky, Andrei Rajkovic, Rodney Tollerson Ii, Lisa A. Jones, Michael Ibba, Daniel B. Kearns

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Translation elongation factor P (EF‐P) in Bacillus subtilis is required for a form of surface migration called swarming motility. Furthermore, B. subtilis EF‐P is post‐translationally modified with a 5‐aminopentanol group but the pathway necessary for the synthesis and ligation of the modification is unknown. Here we determine that the protein YmfI catalyzes the reduction of EF‐P‐5 aminopentanone to EF‐P‐5 aminopentanol. In the absence of YmfI, accumulation of 5‐aminopentanonated EF‐P is inhibitory to swarming motility. Suppressor mutations that enhanced swarming in the absence of YmfI were found at two positions on EF‐P, including one that changed the conserved modification site (Lys …


Elongation Factor P Interactions With The Ribosome Are Independent Of Pausing, Rodney Tollerson Ii, Anne Witzky, Michael Ibba Aug 2017

Elongation Factor P Interactions With The Ribosome Are Independent Of Pausing, Rodney Tollerson Ii, Anne Witzky, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bacterial elongation factor P (EF-P) plays a pivotal role in the translation of polyproline motifs. To stimulate peptide bond formation, EF-P must enter the ribosome via an empty E-site. Using fluorescence-based single-molecule tracking, Mohapatra et al. (S. Mohapatra, H. Choi, X. Ge, S. Sanyal, and J. C. Weisshaar, mBio 8:e00300-17, 2017, https://doi.org/10.1128/mBio.00300-17 ) monitored the cellular distribution of EF-P and quantified the frequency of association between EF-P and the ribosome under various conditions. Findings from the study showed that EF-P has a localization pattern that is strikingly similar to that of ribosomes. Intriguingly, EF-P was seen to bind ribosomes more …


Tumor-Targeted Delivery Of Sirna Using Fatty Acyl-Cgkrk Peptide Conjugates, Meenakshi Sharma, Naglaa Salem El-Sayed, Hung Do, Keykavous Parang, Rakesh Tiwari, Hamidreza Montazeri Aliabadi Jul 2017

Tumor-Targeted Delivery Of Sirna Using Fatty Acyl-Cgkrk Peptide Conjugates, Meenakshi Sharma, Naglaa Salem El-Sayed, Hung Do, Keykavous Parang, Rakesh Tiwari, Hamidreza Montazeri Aliabadi

Pharmacy Faculty Articles and Research

Tumor-targeted carriers provide efficient delivery of chemotherapeutic agents to tumor tissue. CGKRK is one of the well-known tumor targeting peptides with significant specificity for angiogenic blood vessels and tumor cells. Here, we designed fatty acyl conjugated CGKRK peptides, based on the hypothesis that hydrophobically-modified CGKRK peptide could enhance cellular permeation and delivery of siRNA targeted to tumor cells for effective silencing of selected proteins. We synthesized six fatty acyl-peptide conjugates, using a diverse chain of saturated and unsaturated fatty acids to study the efficiency of this approach. At peptide:siRNA weight/weight ratio of 10:1 (N/P ≈ 13.6), almost all the peptides …


Nucleic Acid Combinations: A New Frontier For Cancer Treatment, K. C. Remant Bahadur, Bindu Thapa, Juliana Valencia-Serna, Hamidreza Montazeri Aliabadi, Hasan Uludağ Apr 2017

Nucleic Acid Combinations: A New Frontier For Cancer Treatment, K. C. Remant Bahadur, Bindu Thapa, Juliana Valencia-Serna, Hamidreza Montazeri Aliabadi, Hasan Uludağ

Pharmacy Faculty Articles and Research

The emerging molecular understanding of cancer cell behavior is leading to increasing possibilities to control unchecked cell growth and metastasis. On the other hand, development of multifunctional drug carriers at the ‘nano’-scale is providing exciting new therapeutic strategies in clinical management of cancer beyond the conventional cytotoxic drugs. A new frontier in this regard is the combinational use of complementary agents based on nucleic acids to overcome the limitations of conventional therapy. The existence of tightly-integrated cross-talk through multiple signaling and effector pathways has been appreciated for some time, and the plasticity of such a network to overcome one-dimensional intervention …


Osteoblast-Derived Fgf9 Regulates Skeletal Homeostasis, Liping Wang, Theresa M. Roth, Marcia J. Abbott, Linh Ho, Lalita Wattanachanya, Robert A. Nissenson Feb 2017

Osteoblast-Derived Fgf9 Regulates Skeletal Homeostasis, Liping Wang, Theresa M. Roth, Marcia J. Abbott, Linh Ho, Lalita Wattanachanya, Robert A. Nissenson

Health Sciences and Kinesiology Faculty Articles

FGF9 has complex and important roles in skeletal development and repair. We have previously observed that Fgf9 expression in osteoblasts (OBs) is regulated by G protein signaling and therefore the present study was done to determine whether OB-derived FGF9 was important in skeletal homeostasis. To directly test this idea, we deleted functional expression of Fgf9 gene in OBs using a 2.3 kb collagen type I promoter-driven Cre transgenic mouse line (Fgf9OB −/−). Both Fgf9 knockout (Fgf9OB −/−) and the Fgf9 floxed littermates (Fgf9fl/fl) mice were fully backcrossed and maintained in an FBV/N background. Three …


Editing Of Misaminoacylated Trna Controls The Sensitivity Of Amino Acid Stress Responses In Saccharomyces Cerevisiae, Kyle Mohler, Rebecca Mann, Tammy J. Bullwinkle, Kyle W. Hopkins, Lin Hwang, Noah M. Reynolds, Brandon Gassaway, Hans-Rudolph Aerni, Jesse Rinehart, Michael Polymenis, Kym F. Faull, Michael Ibba Feb 2017

Editing Of Misaminoacylated Trna Controls The Sensitivity Of Amino Acid Stress Responses In Saccharomyces Cerevisiae, Kyle Mohler, Rebecca Mann, Tammy J. Bullwinkle, Kyle W. Hopkins, Lin Hwang, Noah M. Reynolds, Brandon Gassaway, Hans-Rudolph Aerni, Jesse Rinehart, Michael Polymenis, Kym F. Faull, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Amino acid starvation activates the protein kinase Gcn2p, leading to changes in gene expression and translation. Gcn2p is activated by deacylated tRNA, which accumulates when tRNA aminoacylation is limited by lack of substrates or inhibition of synthesis. Pairing of amino acids and deacylated tRNAs is catalyzed by aminoacyl-tRNA synthetases, which use quality control pathways to maintain substrate specificity. Phenylalanyl-tRNA synthetase (PheRS) maintains specificity via an editing pathway that targets non-cognate Tyr-tRNAPhe. While the primary role of aaRS editing is to prevent misaminoacylation, we demonstrate editing of misaminoacylated tRNA is also required for detection of amino acid starvation by …


Quality Control By Isoleucyl-Trna Synthetase Of Bacillus Subtilis Is Required For Efficient Sporulation, Elizabeth Kermgard, Zhou Yang, Annika-Marisa Michel, Rachel Simari, Jacqueline Wong, Michael Ibba, Beth A. Lazazzera Jan 2017

Quality Control By Isoleucyl-Trna Synthetase Of Bacillus Subtilis Is Required For Efficient Sporulation, Elizabeth Kermgard, Zhou Yang, Annika-Marisa Michel, Rachel Simari, Jacqueline Wong, Michael Ibba, Beth A. Lazazzera

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Isoleucyl-tRNA synthetase (IleRS) is an aminoacyl-tRNA synthetase whose essential function is to aminoacylate tRNAIle with isoleucine. Like some other aminoacyl-tRNA synthetases, IleRS can mischarge tRNAIle and correct this misacylation through a separate post-transfer editing function. To explore the biological significance of this editing function, we created a ileS(T233P) mutant of Bacillus subtilis that allows tRNAIle mischarging while retaining wild-type Ile-tRNAIle synthesis activity. As seen in other species defective for aminoacylation quality control, the growth rate of the ileS(T233P) strain was not significantly different from wild-type. When the ileS(T233P) strain was assessed for its ability to promote …


Ms-Read: Quantitative Measurement Of Amino Acid Incorporation, Kyle Mohler, Hans-Rudolph Aerni, Brandon Gassaway, Jiqiang Ling, Michael Ibba, Jesse Rinehart Jan 2017

Ms-Read: Quantitative Measurement Of Amino Acid Incorporation, Kyle Mohler, Hans-Rudolph Aerni, Brandon Gassaway, Jiqiang Ling, Michael Ibba, Jesse Rinehart

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ribosomal protein synthesis results in the genetically programmed incorporation of amino acids into a growing polypeptide chain. Faithful amino acid incorporation that accurately reflects the genetic code is critical to the structure and function of proteins as well as overall proteome integrity. Errors in protein synthesis are generally detrimental to cellular processes yet emerging evidence suggest that proteome diversity generated through mistranslation may be beneficial under certain conditions. Cumulative translational error rates have been determined at the organismal level, however codon specific error rates and the spectrum of misincorporation errors from system to system remain largely unexplored. In particular, until …


Computational Analysis Of Residue Interaction Networks And Coevolutionary Relationships In The Hsp70 Chaperones: A Community- Hopping Model Of Allosteric Regulation And Communication, Gabrielle Stetz, Gennady M. Verkhivker Jan 2017

Computational Analysis Of Residue Interaction Networks And Coevolutionary Relationships In The Hsp70 Chaperones: A Community- Hopping Model Of Allosteric Regulation And Communication, Gabrielle Stetz, Gennady M. Verkhivker

Mathematics, Physics, and Computer Science Faculty Articles and Research

Allosteric interactions in the Hsp70 proteins are linked with their regulatory mechanisms and cellular functions. Despite significant progress in structural and functional characterization of the Hsp70 proteins fundamental questions concerning modularity of the allosteric interaction networks and hierarchy of signaling pathways in the Hsp70 chaperones remained largely unexplored and poorly understood. In this work, we proposed an integrated computational strategy that combined atomistic and coarse-grained simulations with coevolutionary analysis and network modeling of the residue interactions. A novel aspect of this work is the incorporation of dynamic residue correlations and coevolutionary residue dependencies in the construction of allosteric interaction networks …


Engineered Peptides For Applications In Cancer-Targeted Drug Delivery And Tumor Detection, R. Soudy, N. Byeon, Y. Raghuwanshi, S. Ahmed, A. Lavasanifar, Kamaljit Kaur Jan 2017

Engineered Peptides For Applications In Cancer-Targeted Drug Delivery And Tumor Detection, R. Soudy, N. Byeon, Y. Raghuwanshi, S. Ahmed, A. Lavasanifar, Kamaljit Kaur

Pharmacy Faculty Articles and Research

Cancer-targeting peptides as ligands for targeted delivery of anticancer drugs or drug carriers have the potential to significantly enhance the selectivity and the therapeutic benefit of current chemotherapeutic agents. Identification of tumor-specific biomarkers like integrins, aminopeptidase N, and epidermal growth factor receptor as well as the popularity of phage display techniques along with synthetic combinatorial methods used for peptide design and structure optimization have fueled the advancement and application of peptide ligands for targeted drug delivery and tumor detection in cancer treatment, detection and guided therapy. Although considerable preclinical data have shown remarkable success in the use of tumor targeting …