Abstract 234: Ramp2 Is a Novel Flow-sensitive Gene Both In vitro and in vivo
Ramp2 is a member of ramps (receptor activity modified proteins) family, which comprises a single transmembrane domain and involves in protein transport. Specifically, ramp2 is required to transport calcitonin-receptor-like receptor (CRLR) to the plasma membrane, which can function as an adrenomedullin receptor. In addition, ramp2 significantly expresses in endothelial cells but the function of ramp2 in endothelium in response to blood flow has not been reported yet. Here, we first report the expression of ramp2 is significantly altered by different flow conditions. In cultured HUVECs, ramp2 mRNA level decreases over 90% (p<0.01) in oscillatory shear (OS) flow compared to laminar shear (LS). Similarly, ramp2 is down-regulated (reduced 79%, p<0.01) under low and oscillatory shear condition in vivo when performing partial carotid ligation in mouse model. Moreover, a very similar result was obtained from deep sequencing data acquired in zebrafish. Zebrafish embryos were left untreated or injected with tnnt2 morpholinos at one-cell stage that in turn prevents heart beating and stops blood flow. We developed a method to acquire endothelial-enriched mRNAs from these embryos at 2 days post fertilization (dpf), and then samples were subjected to deep sequencing analysis. The data showed that ramp2 decreases 60% (p<0.01) at no flow condition, which is consistent with the observation in mouse and cultured human cells. Together, these data suggests that ramp2 is a novel flow-sensitive gene despite the detail function and significance is still to be determined.
Author Disclosures: C. Ni: None. C. Kim: None. I. Jang: None. H. Jo: None. N.D. Lawson: None.
- © 2015 by American Heart Association, Inc.