Parental Effect of Long Acclimatization on Thermal Tolerance of Juvenile Sea Cucumber Apostichopus japonicus

Abstract

To evaluate the thermal resistance of marine invertebrates to elevated temperatures under scenarios of future climate change, it is crucial to understand parental effect of long acclimatization on thermal tolerance of offspring. To test whether there is parental effect of long acclimatization, adult sea cucumbers (Apostichopus japonicus) from the same broodstock were transplanted southward and acclimatized at high temperature in field mesocosms. Four groups of juvenile sea cucumbers whose parents experienced different durations of high temperature acclimatization were established. Upper thermal limits, oxygen consumption and levels of heat shock protein mRNA of juveniles was determined to compare thermal tolerance of individuals from different groups. Juvenile sea cucumbers whose parents experienced high temperature could acquire high thermal resistance. With the increase of parental exposure duration to high temperature, offspring became less sensitive to high temperature, as indicated by higher upper thermal limits (LT50), less seasonal variations of oxygen consumption, and stable oxygen consumption rates between chronic and acute thermal stress. The relatively high levels of constitutive expression of heat-shock proteins should contribute to the high thermal tolerance. Together, these results indicated that the existence of a parental effect of long acclimatization would increase thermal tolerance of juveniles and change the thermal sensitivity of sea cucumber to future climate change.

Variation in Righting Times of Holothuria atra, Stichopus chloronotus, and Holothuria edulis in Response to Increased Seawater Temperatures on Heron Reef in the Southern GBR

“…Previous research on juvenile sea cucumbers, Apostichopus japonicas, has suggested that increased exposure of parental generations to heat variations will increase the upper thermal limit of their offspring [32]. Similarly, transgenerational mechanisms could improve the tolerance of several holothuroid species during future warming events.…”

Understanding the Heat Shock Response in the Sea Cucumber Apostichopus japonicus, Using iTRAQ-Based Proteomics

“…The sea cucumber A. japonicus in the northern China experienced the highest temperature between 26 and 30 °C in the field [ 11 ]. Besides, A. japonicus enters a state of aestivation when the ambient temperature is maintained at 26 °C [ 3 ].…”

Avian Reproduction in a Warming World

“…For example, if offspring to parents that developed during, or later experienced, a heat wave are born "heat tolerant, " they might be maladapted to the normally colder temperatures of their habitat. Work on ectotherms (e.g., Wang et al, 2015) and plants (e.g., Li and Brawley, 2003) show that parents exposed to warm temperature sire offspring that are more heat-tolerant. To the best of our knowledge, there are no corresponding data for endotherms.…”