The potential role of Annexin 3 in diapause embryo restart of Artemia sinica and in response to stress of low temperature

Abstract

Annexins are highly conserved and ubiquitous in various somatic cell types. They are involved in membrane transport and a range of calcium-regulated activities on the cell membrane surface, including vesicular transport, membrane fusion in exocytosis, signal transduction, and formation of calcium channels. They also regulate inflammatory response, cell differentiation, and interaction between cytoskeletal proteins. In this study, for the first time, an ANX3 gene from Artemia sinica (As-anx3) was cloned. The As-anx3 full-length complementary DNA comprises 1,024 bp and has a 948 bp open reading frame encoding a 315-amino-acid polypeptide with four ANX domains. The profiles of both As-ANX3 mRNA and protein expression exhibited peaks at the 0 hr stage and had the same significant downregulation trend throughout the post-diapause embryo development stage. The ERK1/2, the phosphorylation levels of ERK1/2, and cell cycle-related protein (CDK4) expressions were analyzed by western blot analysis. The results showed that CDK4 presented a significantly ascending trend from 0 and 40 hr, although the phosphorylation levels of ERK1/2 did not increase significantly. The transcriptional and protein expressions of As-ANX3 were highly upregulated when the temperature was lowered from 25 to 15°C, but the expressions showed a gradual downward trend when the temperature was further lowered to 5°C. These results indicated that As-ANX3 plays a crucial role in restarting diapause and low-temperature stress in A. sinica. K E Y W O R D Sannexin 3, Artemia sinica, diapause embryo development

Environmental and molecular regulation of diapause formation in a scyphozoan jellyfish

“…At the molecular level, diapause often involves the activation or repression of specific genes responsible for stress resistance, metabolic arrest and long‐term survival (Fielenbach & Antebi, 2008; Li et al., 2019; Park et al., 2020). In this study, by comparing cells between NPP and PP, we observed that podocyst formation did not substantially alter cell type identity but did lead to changes in the composition of cell types and the relative proportions of cell‐type‐specific gene expression.…”

Investigation of the Possible Role of RAD9 in Post-Diapaused Embryonic Development of the Brine Shrimp Artemia sinica

“…The evolution strategy for A. sinica living through the disadvantageous conditions benefits from the ability of females that produce diapause cysts before the onset of adverse environmental challenges, such as fluctuation of salinity and temperature due to oncoming winter [27,28,29]. To explore the role which RAD9 may be involved in during natural occurrence of diapause, in the present study, the high salinity and low-temperature conditions were repeated to study the expression of As –RAD9 in these stress processes.…”

“…The collection and preparation of A. sinica samples were carried out according to our previous studies [28,37].…”

“…The qPCR was performed in triplicate for each sample using TB Green Premix Ex Taq (Takara, Dalian, China) and Takara detection system TaKaRa TP800 (Takara, Dalian, China). The reaction procedures were initial denaturation at 95 °C for 30 s, then 38 cycles (95 °C for five seconds, 58 °C for 30 s, 95 °C for 15 s, 60 °C for 30 s) [28]. Based on the Ct values of As –RAD 9 and β–actin, the data were analyzed using the comparative cycle threshold (Ct) method (2–Ct ΔΔ method) to calculate the fold increase.…”

“…The cDNA templates were prepared from A. sinica (20 h) in the Nauplius stage, which was incubated at the different gradients of temperatures and salinity as described in our previous studies [4,28], and qPCR was performed to examine relative expression values.…”