Inositol 1,4,5-trisphosphate receptors (IP3Rs) are channels that release Ca2+ from internal stores following agonist-stimulated generation of IP3 by phospholipase C. The Ca2+ signal generated can take the form of a variety of complex waves/oscillations, and the intracellular distribution of IP3Rs is thought to influence its spatial and temporal dynamics. Jan Parys and co-workers now reveal that things are even more complicated (see p. 1269). They have examined the subcellular positioning of IP3Rs in vascular smooth muscle cells stimulated by the hormone arginine-vasopressin. The authors find that, prior to stimulation,IP3R1 and the SERCA-type Ca2+ pump that refills the stores reside in the perinuclear region. After prolonged stimulation, however,they relocalize to the cytoplasm. Parys and co-workers demonstrate that this relocalization can be blocked by agents that inhibit microtubule dynamics or vesicle trafficking. They also show that it depends on protein kinase C (PKC)and that PKC induces outgrowth of microtubules from the perinuclear region into the cytoplasm. The hormone might therefore stimulate PKC-dependent vesicular transport of Ca2+-store components from the perinuclear region to the cytoplasmic ER as some form of adaptive response.
Mobile IP3 receptors
Mobile IP3 receptors. J Cell Sci 1 April 2003; 116 (7): e703. doi:
Download citation file:
Advertisement
Cited by
JCS Journal Meeting 2023: Imaging Cell Dynamics

Our 2023 Journal Meeting on ‘Imaging Cell Dynamics’ will be held from 14-17 May 2023 in Lisbon, Portugal. We have a limited number of spaces left so sign up now! Registration deadline: 31 March.
Call for papers: Cell and Tissue Polarity
-PolarityCFP.png?versionId=4491)
We are welcoming submissions for our next special issue, which will focus on ‘Cell and tissue polarity’ and will be guest edited by David Bryant. Submission deadline: 15 July.
Webinar: Increasing the visibility and impact of your research
-HUBSwebinar.jpg?versionId=4491)
Would you like to increase the visibility and impact of your research and raise your profile internationally? If so, register for the very practical webinar we are running in association with HUBS on 23 February 2023.
Cell scientist to watch: Gautam Dey

We interviewed Gautam Dey, who became a group leader at EMBL in Heidelberg, Germany, in 2021. His lab investigates the fundamental organisational principles and evolutionary dynamics of the nuclear compartment across eukaryotes.
Mechanisms of eukaryotic transcription termination at a glance

Check out our latest Cell Science at a Glance article and accompanying poster for an overview of the current understanding about the mechanisms of transcription termination by the three eukaryotic RNAPs.