The objectives of the present study were to determine if IQGAP1 associates with components of the endothelial adherens junction and if it affects endothelial barrier function. In human umbilical vein endothelial cells (HUVECs), soluble IQGAP1 associated with VE-cadherin and the catenins, b, y, and a, but not N-cadherin. Gene silencing of IQGAP1 by transfection of small interfering RNA (siRNA) with oligofectamine maintained a higher endothelial electrical resistance in HUVECs as compared to transfection of a scrambled siRNA. Reduction of IQGAP1 induced an increase and a decrease, respectively, in the protein levels of VE-cadherin and N-cadherin. More VE-cadherin and less N-cadherin were associated with p120- and B -catenins in IQGAP1 knockdown cells. Furthermore, more insoluble (actin-associated) VE-cadherin was localized at intercellular junctions and less insoluble N-cadherin was present in the cell. These findings suggest that a reduction of IQGAP1 positively influences the endothelial barrier by increasing the protein level of VE-cadherin and the interaction of VE-cadherin with the actin cytoskeleton. The increased interaction with the catenins, B and p120, possibly resulting from the decrease in N-cadherin, may explain the increase in VE-cadherin.
Links with this icon indicate that you are leaving the CDC website.
The Centers for Disease Control and Prevention (CDC) cannot attest to the accuracy of a non-federal website.
Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website.
You will be subject to the destination website's privacy policy when you follow the link.
CDC is not responsible for Section 508 compliance (accessibility) on other federal or private website.
For more information on CDC's web notification policies, see Website Disclaimers.
CDC.gov Privacy Settings
We take your privacy seriously. You can review and change the way we collect information below.
These cookies allow us to count visits and traffic sources so we can measure and improve the performance of our site. They help us to know which pages are the most and least popular and see how visitors move around the site. All information these cookies collect is aggregated and therefore anonymous. If you do not allow these cookies we will not know when you have visited our site, and will not be able to monitor its performance.
Cookies used to make website functionality more relevant to you. These cookies perform functions like remembering presentation options or choices and, in some cases, delivery of web content that based on self-identified area of interests.
Cookies used to track the effectiveness of CDC public health campaigns through clickthrough data.
Cookies used to enable you to share pages and content that you find interesting on CDC.gov through third party social networking and other websites. These cookies may also be used for advertising purposes by these third parties.
Thank you for taking the time to confirm your preferences. If you need to go back and make any changes, you can always do so by going to our Privacy Policy page.