(c) 2008 Japanese Society for Investigative Dermatology. Published by Elsevier Ireland Ltd. All rights reserved.”
“Connexin26 (Cx26) mutation is the most common cause for non-syndromic hereditary deafness. Different congenital Cx26 null mouse models revealed
a profound hearing loss pattern and developmental defect in the cochlea. Our study aimed at establishing a Cx26 knocking down mouse model at different postnatal time points and to investigate the time course and pattern of the hearing loss and cell degeneration in these models. Morphologic changes were observed for 5 months to detect long-term diversities among these models. Depending on the time point when Cx26 expression was reduced, mild to profound hearing loss patterns were found in different groups. Malformed organ of Corti with distinct RG7321 cell loss in middle turn was observed only in early Cx26 reduction group while mice in late Cx26 reduction group developed normal organ of Corti and only suffered a few hair loss in the basal turn. These results indicated that Cx26 may play essential roles in the postnatal maturation of the cochlea, and its role in normal hearing at more mature stage may be replaceable. (C) 2014 Elsevier Inc. All rights reserved.”
“Very late antigen-4 (VLA-4), a member of integrin superfamily, interacts
with its major counter ligand vascular cell adhesion molecule-1 (VCAM-1) and ARN-509 plays an important role in leukocyte adhesion to vascular endothelium and immunological synapse formation. However, irregular
expressions of these proteins may also lead to several autoimmune diseases and metastasis cancer. Thus, quantifying the interaction affinity of the VCAM-1/VLA-4 interaction is of fundamental importance in further understanding the nature of this interaction and drug discovery. In this study, we report an ‘in solution’ steady state organic fluorophore based quantitative fluorescence resonance energy transfer (FRET) assay to quantify this interaction in terms of the dissociation constant (K-d). We have used, in our FRET assay, the Alexa Fluor 488-VLA-4 conjugate as the donor, and Alexa Fluor 546-VCAM-1 as the acceptor. From the FRET signal analysis, K-d of this interaction was determined to be 41.82 +/- 2.36 nM. To further confirm our estimation, we have PXD101 cost employed surface plasmon resonance (SPR) technique to obtain K-d = 39.60 +/- 1.78 nM, which is in good agreement with the result obtained by FRET. This is the first reported work which applies organic fluorophore based ‘in solution’ simple quantitative FRET assay to obtain the dissociation constant of the VCAM-1/VLA-4 interaction, and is also the first quantification of this interaction. Moreover, the value of K-d can serve as an indicator of abnormal protein-protein interactions; hence, this assay can potentially be further developed into a drug screening platform of VLA-4/VCAM-1 as well as other protein-ligand interactions.