Skip to main content
. 2016 Sep 1;7:12702. doi: 10.1038/ncomms12702

Figure 5. ORP4L sustains Ca2+-dependent bioenergetics in T-ALL cells.

Figure 5

(a,b) Western blot analysis of PDH activation in Jurkat, Molt-4 and primary T-ALL cells with ORP4L knockdown (a) and overexpression (b). p-PDH/PDH expressed as fold change over control. (c) PDH activation (left), OCR (middle) and ATP levels (right) in Jurkat T-cells with ORP4L knockdown alone or in combination with shPLCβ3. (d) PDH activation (left), OCR (middle) and ATP levels (right) in control or ORP4L overexpressing Jurkat T-cells treated with or without U73122 (5 μM for 1 h) or XeC (2 μM for 1 h). (e) PDH activation (left), OCR (middle) and ATP levels (right) in control or ORP4L knockdown Jurkat T-cells treated with or without ionomycin (2 mg l−1 for 1 h). (f) PDH activation (left), OCR (middle) and ATP levels (right) in control or ORP4L overexpressing Jurkat T-cells treated with or without BAPTA-AM (50 μM for 1 h). (g) PDH activation (left), OCR (middle) and ATP levels (right) in control or ORP4L knockdown Jurkat T-cells treated with or without MCU agonist, kaempferol (2 μM, 30 min). (h) PDH activation (left), OCR (middle) and ATP levels (right) in control or ORP4L overexpressing Jurkat T-cells treated with or without MCU inhibitor, RU360 (5 μM, 30 min). The data represent mean±s.d. value from an experiment performed in triplicate. *P<0.05, **P<0.01, ***P<0.001, Student's t test. (i) Model outlining the functions of ORP4L. In T-ALL cells, CD3ζ chain expression is defective, and ORP4L couples CD3ɛ to PLCβ3/Gαq/11 to control the relocation and activation of PLCβ3, which leads to increased IP3 generation and Ca2+ release from ER required for sustaining of cell bioenergetics.