Juvenile Hormone Membrane Signaling Enhances its Intracellular Signaling Through Phosphorylation of Met and Hsp83

Yue Gao; Nan Chen; Xiangle Zhang; Emma Y Li; Wei Luo; Jie Zhang; Wenqiang Zhang; Sheng Li; Jian Wang; Suning Liu

doi:10.3389/fphys.2022.872889

Juvenile Hormone Membrane Signaling Enhances its Intracellular Signaling Through Phosphorylation of Met and Hsp83

Front Physiol. 2022 Apr 27:13:872889. doi: 10.3389/fphys.2022.872889. eCollection 2022.

Authors

Yue Gao¹, Nan Chen¹, Xiangle Zhang¹, Emma Y Li², Wei Luo¹, Jie Zhang¹, Wenqiang Zhang¹, Sheng Li^{1

3}, Jian Wang⁴, Suning Liu^{1

3}

Affiliations

¹ Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, Institute of Insect Science and Technology, School of Life Sciences, South China Normal University, Guangzhou, China.
² International Department, The Affiliated High School of South China Normal University, Guangzhou, China.
³ Guangmeiyuan R&D Center, Guangdong Provincial Key Laboratory of Insect Developmental Biology and Applied Technology, South China Normal University, Meizhou, China.
⁴ Department of Entomology, University of Maryland, College Park, MD, United States.

Abstract

Juvenile hormone (JH) regulates insect development and reproduction through both intracellular and membrane signaling, and the two pathways might crosstalk with each other. Recent studies have reported that JH membrane signaling induces phosphorylation of the JH intracellular receptor Met, thus enhancing its transcriptional activity. To gain more insights into JH-induced Met phosphorylation, we here performed phosphoproteomics to identify potential phosphorylation sites of Met and its paralog Germ-cell expressed (Gce) in Drosophila Kc cells. In vitro experiments demonstrate that JH-induced phosphorylation sites in the basic helix-loop-helix (bHLH) domain, but not in the Per-Arnt-Sim-B (PAS-B) domain, are required for maximization of Met transcriptional activity. Moreover, phosphoproteomics analysis reveale that JH also induces the phosphorylation of Hsp83, a chaperone protein involved in JH-activated Met nuclear import. The JH-induced Hsp83 phosphorylation at S219 facilitates Hsp83-Met binding, thus promoting Met nuclear import and its transcription. By using proteomics, subcellular distribution, and co-immunoprecipitation approaches, we further characterized 14-3-3 proteins as negative regulators of Met nuclear import through physical interaction with Hsp83. These results show that JH membrane signaling induces phosphorylation of the key components in JH intracellular signaling, such as Met and Hsp83, and consequently facilitating JH intracellular signaling.

Keywords: 14-3-3 proteins; Met/Gce; biotinylation; hsp83; phosphoproteomics; phosphorylation; proteomics.