珊瑚可以适应吗?
Katherine Dziedzic, a PhD student from Oregon State University (OSU), is looking at how珊瑚s can adapt to climate change。为了了解珊瑚如何适应温暖的海洋温度,她正在研究不同珊瑚物种的DNA和RNA,以找出哪种(如果有的话)对海洋变暖更宽容。
Symbiotic Relationship
珊瑚由一个称为息肉的小动物群制成。息肉与光合海洋藻类生活在一起。为了换取息肉内的保护,这些藻类吸收阳光并为息肉产生能量。
Polyps can also get energy from ingesting plankton and food particles drifting in the current, however since they are fixed in one place their energy from food consumption is limited. Coral polyps are reliant on the sunlight to survive, and without the algae they would die.
When we hear about ‘coral bleaching’ an image of a ghostly white coral comes to mind. When a coral is under stress from elevated ocean temperatures the algal symbionts start producing a toxin causing the coral to expel the algae from their tissues, leaving the coral devoid of color and on the brink of survival.
Thermal Acclimation of Coral Reef Ecosystems
有趣的是,有些珊瑚可以更好地在海洋温度中生存这些突然波动,并且单个珊瑚菌落可能比邻居更好。This has to do with the genetic makeup of each coral, and the genes they express that allows them to be resilient to changing conditions.
With the increasing reality that our oceans are getting warmer, it is important we begin safeguarding coral reefs for future generations.Katherine Dziedzic is looking atnine coral species为了评估遗传变异是否有助于珊瑚的适应能力,这可能会导致长期适应过程。
She uses an RNA-sequencing method to measure the expression of genes with response to a thermal stress. In particular, she is assessing how genes are regulated during thermal acclimation and if that gene plays a role in helping each coral species acclimate to a given temperature more effectively. In addition, she is interested in how the symbiont and the coral host are each contributing to the acclimation response.
Katherine studies live corals in her laboratory at OSU using saltwater aquariums. In various tanks, she adjusts the water temperature to a hotter than normal temperature (acclimation) before exposing them to a thermal stress. At multiple time points, she takes tissue samples to extract DNA and RNA for sequencing, allowing her to compare each coral host and symbiont for acclimation differences.
Exploring the functional basis and differences in acclimation will provide more insight into potential mechanisms that may allow more thermally tolerant corals to persist into the future.
Understanding which genes are ‘turned on’ in thermally tolerant corals can provide new insight to how quickly corals can adapt, and how they acquired these genes. This information could lead to coral restoration effort which involve transplanting thermally tolerant genotypes.