![]() Here we report the successful use of spectral variants of the new generation of intensiometric single fluorescent protein GECIs (e.g. However, ER can also work as a Ca 2+ source, being responsible for the generation of a cytosolic Ca 2+ transient ( Shkolnik et al., 2018 Luo et al., 2020). Overall, in plants, in vivo analyses of ER Ca 2+ dynamics revealed that it primarily acts as a Ca 2+ sink, thus contributing to the dampening of the Ca 2+ transient ( Bonza et al., 2013 Corso et al., 2018). (2020), who generated a new Arabidopsis line expressing the intensiometric ER-localized sensor R-CEPIA1er ( Luo et al., 2020). Some of these data were later confirmed by Luo et al. By using the ratiometric CRT-D4ER Cameleon, we previously reported, in root-tip cells, the ER Ca 2+ dynamics in response to different stimuli, such as external ATP, l-glutamate, salt stress, and water potential gradient ( Bonza et al., 2013 Corso et al., 2018 Shkolnik et al., 2018). Later, by using Förster resonance energy transfer (FRET)-based genetically encoded Ca 2+ indicator (GECI SP-YC4.6 and calreticulin -D4ER Cameleon) localized to the ER lumen, the ER resting Ca 2+ concentration () was measured in vivo in Arabidopsis ( Arabidopsis thaliana) pollen tubes and in leaf and root cells ( Iwano et al., 2009 Bonza et al., 2013 Tian et al., 2014). CCXs) have been shown to participate in the regulation of Ca 2+ transport across the ER membranes ( Corso et al., 2018).Ĭa 2+ transport over the ER membrane was observed using purified microsomal vesicles loaded with the 45Ca 2+ isotope ( Navazio et al., 2000). cyclic nucleotide-gated channels) localized in the nuclear envelope (NE, which is in continuity with the ER Charpentier et al., 2016 Leitão et al., 2019) and Ca 2+/cation transporters (e.g. In addition, Ca 2+-permeable channels (e.g. However, a battery of P-Type IIA (ER-type Ca 2+-ATPases, ECAs) and IIB (autoinhibited Ca 2+ ATPases, ACAs) Ca 2+-ATPases are localized in the ER membranes and their primary function is to import Ca 2+ into the ER lumen ( Bonza and De Michelis, 2011 Bonza et al., 2013 Shkolnik et al., 2018). In plants, RyR, InsP 3R, and the STIM–Orai complex are not present ( Edel et al., 2017). Moreover, in animals, Ryanodine (RyR) and inositol trisphosphate (InsP 3R) receptors are ER-localized, ligand-gated Ca 2+ permeable channels that release Ca 2+ into the cytosol ( Foskett et al., 2007), whereas the ER Ca 2+ refilling is dependent on the activity of sarco/ER Ca 2+-ATPases (SERCA) and the stromal interaction molecule (STIM)–Orai protein complex ( Soboloff et al., 2012). ![]() In animals, besides its role in protein secretion, the endoplasmic reticulum (ER) is a calcium ions (Ca 2+) store participating in the generation and shaping of stimulus-induced cytosolic Ca 2+ increases ( Soboloff et al., 2012). This technology enhances high-resolution analyses of intracellular Ca 2+ dynamics at the cellular level and in adult organisms and paves the way to develop new methodologies aimed at defining the contribution of subcellular compartments in Ca 2+ homeostasis and signaling. Furthermore, live imaging of mature, soil-grown plants revealed the existence of a wounding-induced, long-distance ER Ca 2+ wave propagating in injured and systemic rosette leaves. By performing analyses in single cells, we precisely quantified (1) the time required by the ER to import Ca 2+ from the cytosol into the lumen and (2) the time required to observe a cytosolic Ca 2+ increase upon the pharmacological inhibition of the ER-localized P-Type IIA Ca 2+-ATPases. By exploiting state-of-the-art genetically encoded Ca 2+ indicators, specifically the ER-GCaMP6-210 and R-GECO1, we report the generation and characterization of an Arabidopsis ( Arabidopsis thaliana) line that allows for simultaneous imaging of Ca 2+ dynamics in both the ER and cytosol at different spatial scales. The ER represents an intracellular Ca 2+ store that actively accumulates Ca 2+ taken up from the cytosol. In plants, a plethora of environmental and developmental stimuli induce specific Ca 2+ increases in the cytosol as well as in different cellular compartments including the endoplasmic reticulum (ER). Calcium ions (Ca 2+) play a key role in cell signaling across organisms.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |