Sensing a sensor: Identifying the mechanosensory function of primary cilia

20Citations
Citations of this article
55Readers
Mendeley users who have this article in their library.

Abstract

Over the past decade, primary cilia have emerged as the premier means by which cells sense and transduce mechanical stimuli. Primary cilia are sensory organelles that have been shown to be vitally involved in the mechanosensation of urine in the renal nephron, bile in the hepatic biliary system, digestive fluid in the pancreatic duct, dentin in dental pulp, lacunocanalicular fluid in bone and cartilage, and blood in vasculature. The prevalence of primary cilia among mammalian cell types is matched by the tremendously varied disease states caused by both structural and functional defects in cilia. In the process of delineating the mechanisms behind these disease states, calcium fluorimetry has been widely utilized as a means of quantifying ciliary function to both fluid flow and pharmacological agents. In this review, we will discuss the approaches used in associating calcium levels to cilia function. © 2014 by the authors.

Figures

  • Figure 1. Structure of cilia. (a) Cilia are cellular organelles composed of microtubules, and they project from the apical surface of numerous cell types. (b) A cilium is composed of a membrane domain, a soluble compartment or cilioplasm, an axoneme and a basal body. The membrane domain contains multiple sensory and channel proteins, several of which play a role in calcium-mediated fluid-flow mechanosensation. (c) The orientation of the microtubules in the axoneme is categorized as “9+0” or “9+2” and is anchored to the basal body. Taken and adapted from [1].
  • Figure 2. Calcium response to fluid flow in cell cultures. (a) The induction of fluid flow causes a rise in calcium in cells (pseudocolored). (b) In transgenic cell lines with knocked-out Pkd1 or Tg737, both of which are ciliary proteins, calcium response is lost. The cells were incubated with fluorescent calcium dyes. Blue represents a low level; red denotes a higher level of calcium. Taken and adapted from [7].
  • Figure 3. Ciliary calcium response to fluid flow in a single cell. (a) The calcium responses within the ciliary and cytoplasmic compartments of cells (pseudocolored) can be observed utilizing fluorescent calcium dyes or cell lines containing transgenic calcium indicators. (b) The induction of fluid flow causes bending of the primary cilium and a subsequent influx of calcium, first through the cilioplasm and then into the cell body. Color bar indicates calcium level, where black–purple and yellow–red colors represent low and high calcium levels, respectively. Bar = 4 μm. Taken and adapted from [60].
  • Figure 4. Calcium response to fluid flow in ex vivo arteries. (a) Within ex vivo arteries, fluid flow causes an influx of calcium. (b) In tissues with knocked-down Pkd2, a ciliary calcium channel, or that are treated with apyrase, the response profile is changed. Tissues were incubated with a fluorescent calcium dye prior to perfusion. Change in cytosolic calcium was pseudocolored; white/green represents a low level of cytosolic calcium, and yellow/red denotes a higher level. Taken and adapted from [6].
  • Figure 5. Calcium response to fluid flow in capillary-enclosed arteries ex vivo. (a) Within the capillary-enclosed arteries ex vivo, fluid flow causes an influx of calcium. (b) In tissues with knocked-down Pkd2 or in tissues treated with apyrase, the response profile is changed. Tissues were incubated with a fluorescent calcium dye prior to perfusion. Change in cytosolic calcium was pseudocolored; white/green represents a low level, and yellow/red denotes a higher level of cytosolic calcium. Taken and adapted from [6].
  • Table 1
  • Table 2

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Cite

CITATION STYLE

APA

Prasad, R. M., Jin, X., & Nauli, S. M. (2014). Sensing a sensor: Identifying the mechanosensory function of primary cilia. Biosensors. MDPI. https://doi.org/10.3390/bios4010047

Readers over time

‘14‘15‘16‘17‘18‘19‘20‘21‘22‘24‘2505101520

Readers' Seniority

Tooltip

PhD / Post grad / Masters / Doc 20

56%

Researcher 12

33%

Professor / Associate Prof. 2

6%

Lecturer / Post doc 2

6%

Readers' Discipline

Tooltip

Agricultural and Biological Sciences 16

47%

Biochemistry, Genetics and Molecular Bi... 9

26%

Medicine and Dentistry 5

15%

Engineering 4

12%

Save time finding and organizing research with Mendeley

Sign up for free
0