Male moth sensitivity to multicomponent pheromones: Critical role of female-released blend in determining the functional role of components and active space of the pheromone

1986 ◽  
Vol 12 (3) ◽  
pp. 659-668 ◽  
Author(s):  
C. E. Linn ◽  
M. G. Campbell ◽  
W. L. Roelofs
2021 ◽  
Author(s):  
Chih-Wei Huang ◽  
Chi-Ching Hwang ◽  
Yung-Lung Chang ◽  
Jen-Tzu Liu ◽  
Sheng-Peng Wu ◽  
...  

4-Hydroxylphenylpyruvate dioxygenase (HPPD) catalyzes the conversion of 4-hydroxylphenylpyruvate (HPP) to homogentisate, the important step for tyrosine catabolism. Comparison of the structure of human HPPD with the substrate-bound structure of A. thaliana HPPD revealed notably different orientations of the C-terminal helix. This helix performed as a closed conformation in human enzyme. Simulation revealed a different substrate-binding mode in which the carboxyl group of HPP interacted by a H-bond network formed by Gln334, Glu349 (the metal-binding ligand), and Asn363 (in the C-terminal helix). The 4-hydroxyl group of HPP interacted with Gln251 and Gln265. The relative activity and substrate-binding affinity were preserved for the Q334A mutant, implying the alternative role of Asn363 for HPP binding and catalysis. The reduction in kcat/Km of the Asn363 mutants confirmed the critical role in catalysis. Compared to the N363A mutant, the dramatic reduction in the Kd and thermal stability of the N363D mutant implies the side-chain effect in the hinge region rotation of the C-terminal helix. The activity and binding affinity were not recovered by double mutation; however, the 4-hydroxyphenylacetate intermediate formation by the uncoupled reaction of Q334N/N363Q and Q334A/N363D mutants indicated the importance of the H-bond network in the electrophilic reaction. These results highlight the functional role of the H-bond network in a closed conformation of the C-terminal helix to stabilize the bound substrate. The extremely low activity and reduction in Q251E’s Kd suggest that interaction coupled with the H-bond network is crucial to locate the substrate for nucleophilic reaction.


2018 ◽  
Vol 46 (3) ◽  
pp. 1122-1133 ◽  
Author(s):  
Bing Zeng ◽  
Zewei Lin ◽  
Huilin Ye ◽  
Di Cheng ◽  
Guangtao Zhang ◽  
...  

Background/Aims: Long noncoding RNAs (lncRNAs) are key regulators of cancer initiation and progression. In this study, we investigated the clinical value and functional role of LncRNA DQ786243 (LncDQ) in the pathogenesis of hepatocellular carcinoma (HCC). Methods: To investigate the expression level of LncDQ in HCC, we performed quantitative real-time PCR using total RNA extracted from HCC tumor tissues and their matched non-neoplastic counterparts, as well as from the serum of HCC patients and healthy volunteers. The correlation of LncDQ expression with clinicopathologic features and prognosis was analyzed. The functional role of LncDQ in cell proliferation, migration, and invasion were evaluated by MTT cell viability, wound healing, and transwell assays in vitro and in vivo. RNA immunoprecipitation and chromatin immunoprecipitation assays were performed to analyze the potential mechanism of LncDQ in HCC cells. Results: LncDQ was upregulated in both HCC tissue samples and serum and was correlated with low survival rate and adverse clinical pathological characteristics. Multivariate analysis demonstrated that LncDQ expression was an independent prognostic factor for HCC. The area under the receiver operating characteristic curve was 0.804 with a sensitivity of 0.72 and a specificity of 0.8. Knockdown of LncDQ induced inhibition of cell proliferation, migration, and invasion in vitro and in vivo. Mechanistically, LncDQ regulated the epithelial–mesenchymal transition pathway by interacting with EZH2, to epigenetically repress the expression of E-cadherin in HCC cells. Conclusions: Taken together, the results of our study indicate that LncDQ plays a critical role in HCC progression, and may serve as a potential diagnostic and prognostic biomarker for HCC.


PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242141
Author(s):  
Alakesh Bera ◽  
Madhan Subramanian ◽  
John Karaian ◽  
Michael Eklund ◽  
Surya Radhakrishnan ◽  
...  

Breast Cancer is the most common form of cancer in women worldwide, impacting nearly 2.1 million women each year. Identification of new biomarkers could be key for early diagnosis and detection. Vitronectin, a glycoprotein that is abundantly found in serum, extracellular matrix, and bone, binds to integrin αvβ3, and promotes cell adhesion and migration. Current studies indicate that patients with amplified vitronectin levels have lower survival rates than patients without amplified vitronectin levels. In this study, we focused on the role of vitronectin in breast cancer survival and its functional role as a non-invasive biomarker for early stage and stage specific breast cancer detection. To confirm that the expression of vitronectin is amplified in breast cancer, a total of 240 serum samples (n = 240), 200 from breast cancer patients and 40 controls were analyzed using the Reverse Phase Protein Array (RPPA) technique. Of the 240 samples, 120 samples were of African American (AA) descent, while the other 120 were of White American (WA) descent. Data indicated that there were some possible racial disparities in vitronectin levels and, differences also seen in the recurrent patient samples. Next, we tried to uncover the underlying mechanism which plays a critical role in vitronectin expression. The cellular data from four different breast cancer cell lines- MCF7, MDA-MB-231, MDA-MB-468, and HCC1599 indicated that the PI3K/AKT axis is modulating the expression of vitronectin. We believe that vitronectin concentration levels are involved and connected to the metastasis of breast cancer in certain patients, specifically based on recurrence or ethnicity, which is detrimental for poor prognosis. Therefore, in this current study we showed that the serum vitronectin levels could be an early marker for the breast cancer survival and we also determine the cellular signaling factors which modulate the expression and concentration of vitronectin.


Biomedicines ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 100
Author(s):  
Lindy K. Brastrom ◽  
C. Anthony Scott ◽  
Kai Wang ◽  
Diane C. Slusarski

Congenital eye defects represent a large class of disorders affecting roughly 21 million children worldwide. Microphthalmia and anophthalmia are relatively common congenital defects, with approximately 20% of human cases caused by mutations in SOX2. Recently, we identified the RNA-binding motif protein 24a (Rbm24a) which binds to and regulates sox2 in zebrafish and mice. Here we show that morpholino knockdown of rbm24a leads to microphthalmia and visual impairment. By utilizing sequential injections, we demonstrate that addition of exogenous sox2 RNA to rbm24a-deplete embryos is sufficient to suppress morphological and visual defects. This research demonstrates a critical role for understanding the post-transcriptional regulation of genes needed for development.


2008 ◽  
Vol 15 (2) ◽  
pp. 50-59 ◽  
Author(s):  
Amy Philofsky

AbstractRecent prevalence estimates for autism have been alarming as a function of the notable increase. Speech-language pathologists play a critical role in screening, assessment and intervention for children with autism. This article reviews signs that may be indicative of autism at different stages of language development, and discusses the importance of several psychometric properties—sensitivity and specificity—in utilizing screening measures for children with autism. Critical components of assessment for children with autism are reviewed. This article concludes with examples of intervention targets for children with ASD at various levels of language development.


1998 ◽  
Vol 5 (1) ◽  
pp. 115A-115A
Author(s):  
K CHWALISZ ◽  
E WINTERHAGER ◽  
T THIENEL ◽  
R GARFIELD
Keyword(s):  

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