| 1. |
- Case, Laura K., et al.
(författare)
-
Innocuous pressure sensation requires A-type afferents but not functional Rho Iota Epsilon Zeta Omicron 2 channels in humans
- 2021
-
Ingår i: Nature Communications. - : Nature Research. - 2041-1723. ; 12:1
-
Tidskriftsartikel (refereegranskat)abstract
- The sensation of pressure allows us to feel sustained compression and body strain. While our understanding of cutaneous touch has grown significantly in recent years, how deep tissue sensations are detected remains less clear. Here, we use quantitative sensory evaluations of patients with rare sensory disorders, as well as nerve blocks in typical individuals, to probe the neural and genetic mechanisms for detecting non-painful pressure. We show that the ability to perceive innocuous pressures is lost when myelinated fiber function is experimentally blocked in healthy volunteers and that two patients lacking A beta fibers are strikingly unable to feel innocuous pressures at all. We find that seven individuals with inherited mutations in the mechanoreceptor PIEZO2 gene, who have major deficits in touch and proprioception, are nearly as good at sensing pressure as healthy control subjects. Together, these data support a role for A beta afferents in pressure sensation and suggest the existence of an unknown molecular pathway for its detection. The mechanisms underlying deep pressure sensing are not fully understood. Here the authors demonstrate that while two individuals lacking A beta fibers demonstrate impaired deep pressure sensing, seven individuals with PIEZO2 loss of function mutations display normal deep pressure responses.
|
|
| 2. |
- Scott, Mark G H, et al.
(författare)
-
Cooperative regulation of extracellular signal-regulated kinase activation and cell shape change by filamin A and beta-arrestins.
- 2006
-
Ingår i: Molecular and cellular biology. - 0270-7306. ; 26:9, s. 3432-45
-
Tidskriftsartikel (refereegranskat)abstract
- beta-Arrestins (betaarr) are multifunctional adaptor proteins that can act as scaffolds for G protein-coupled receptor activation of mitogen-activated protein kinases (MAPK). Here, we identify the actin-binding and scaffolding protein filamin A (FLNA) as a betaarr-binding partner using Son of sevenless recruitment system screening, a classical yeast two-hybrid system, coimmunoprecipitation analyses, and direct binding in vitro. In FLNA, the betaarr-binding site involves tandem repeat 22 in the carboxyl terminus. betaarr binds FLNA through both its N- and C-terminal domains, indicating the presence of multiple binding sites. We demonstrate that betaarr and FLNA act cooperatively to activate the MAPK extracellular signal-regulated kinase (ERK) downstream of activated muscarinic M1 (M1MR) and angiotensin II type 1a (AT1AR) receptors and provide experimental evidence indicating that this phenomenon is due to the facilitation of betaarr-ERK2 complex formation by FLNA. In Hep2 cells, stimulation of M1MR or AT1AR results in the colocalization of receptor, betaarr, FLNA, and active ERK in membrane ruffles. Reduction of endogenous levels of betaarr or FLNA and a catalytically inactive dominant negative MEK1, which prevents ERK activation, inhibit membrane ruffle formation, indicating the functional requirement for betaarr, FLNA, and active ERK in this process. Our results indicate that betaarr and FLNA cooperate to regulate ERK activation and actin cytoskeleton reorganization.
|
|
