Juicy Pineapple Genome Provides Insight into Drought Resistance

The pineapple plant is an interesting and complicated plant known to have gone through many evolutionary adaptations in order to thrive in the water-limited environments it is grown in. The plant has a very complicated evolutionary history, which it shares with grasses such as sorghum and rice. Drought has become a major issue that is responsible for a majority of global crop loss and, therefore, researchers have been looking for ways to make currently existing essential crops drought-resistant. Recently an international team of scientists has completed the genome sequence of the pineapple plant, which has allowed for more insight into its evolutionary history which has allowed it to become drought resistant.

Genetically, ancestors of the pineapple and grasses like rice and sorghum experienced several doublings of their genomes and by tracking the remnants of these whole-genome duplications the team was able to trace the evolutionary histories of these drought resistant crops. By doing this the group was capable of finding that the pineapple genome actually has one less whole-genome duplication than the grasses that share common ancestors with the plant, thus making it the best comparison group to study the genetics of drought resistance in plants.

By completing the genome of pineapple plant the researchers also found more information regarding the crassulacean acid metabolism (CAM) method of photosynthesis the plant uses. Pineapples use the CAM method of photosynthesis, in which plants can close the pores in their leaves during the day and open them at night allowing them to lose very little moisture during the day and absorb and fix CO2 at night to release the following day during photosynthesis. The process has evolved independently in 10,000 plant species, and differs from the C3 and C4 pathways of photosynthesis used by crop and tropical plants.  From the completed genome the researchers found that some of the genes that contribute to CAM photosynthesis are actually regulated by the genes the govern the plant's circadian clock. This is the first time scientists have found a link between regulatory elements of CAM photosynthesis genes and the regulation of the circadian clock, which allows the plants to determine the time of day and adjust it's metabolism accordingly.

Finally, the researchers also discovered that CAM photosynthesis evolved strictly through genetic reconfiguration of the molecular pathways of C3 photosynthesis. This means that all plants contain the genes that are needed for CAM photosynthesis and the evolution CAM photosynthesis can be achieved in different plants species by rerouting the plants preexisting pathways. This finding can lead to huge developments in producing drought-tolerant varieties of several essential crops.

I find this article very exciting and interesting. This is article discusses plant genetics in great depth and is very interesting and informative in regards to the evolution of plants genomes and genetics. I find it so interesting to think that by completing a single genome these researchers were capable of discovering the history of the evolution of the pineapple plant and find the genetic process behind how the pineapple plant developed the ability to be drought resistant and perform CAM photosynthesis. The findings are also very interesting and can lead to so many possibilities in producing drought resistant crops.

For a link the original article click here
To find out more about the different types of photosynthesis click here
For more articles regarding the completion of the pineapple genome click here

Chrono, the last piece of the circadian clock puzzle?

This article talks about how all organisms have a daily cycles that are regulated by the circadian clock. This internal clock is best known for its ability to be influenced by exposure to light which controls the wake-sleep cycle. The clock that controls such an activity is controlled by genes and proteins that interact and turn each other on and off based on the environment.

A team from RIKEN, Hiroshima University, and University of Michigan conducted a study in order to uncover a missing component. The researchers decided to perform a genome-wide chromatin immunoprecipitation analysis for genes that target a core component of the clock genes, called BMAL1. From this, the authors discovered a new circadian gene which functions as a transcriptional repressor of the negative feedback loop in the mammalian clock. This protein, which they named CHRONO, was shown to alter the expression of core clock genes in mice that lacked the gene. This resulted in longer circadian cycles.

The article also states that the study demonstrated "that the repression mechanism of CHRONO is under epigenetic control and links, via a glucocorticoid receptor, to metabolic pathways triggered by behavioral stress."

The sleep cycle is not well understood in the scientific world, and while this research doesn't pinpoint exactly why we sleep it does offer some preliminary insight on the mechanisms of why we sleep when we do and how the mechanisms function as a unit to control the internal clock. Continuing research could reveal some interesting findings of our circadian clock and sleep cycles.

Sleepy Genes

Sleep. We all do it. We all need it. As college students, we learn very quickly that sleep is of the essence, when we can get it. But is it really?

 

A study has recently been published in ScienceDaily contributing to this very question. Researchers from Rockefeller University have identified a new gene called insomniac that seems to have a correlation with regulatory sleeping habits in a new, methodical way than we have previously known. Mutations in this insomniac gene were first seen in the laboratory using infrared beams to detect when the flies fell to sleep. This gene caused a significant decrease in the amount of sleep that flies averagely displayed. It also seemed to affect to periods of time they were about to stay asleep, making the number of times they wake up more frequent and disturbed. Lastly, and most interestingly, this newly founded gene seems to be a process not of the well-known circadian cycle, but of bodily homeostatic mechanisms. The main difference being that usual sleep-involved processes occur through the circadian cycle, which regulates sleeping between day and night. Homeostatic mechanisms occur at every hour since their job consists mainly on keeping the body at a healthy balance.

 

However, now to their next discovery, which makes one stop and contemplate just how important sleep is to organisms. At first in their study, they discovered that the insomniac gene decreased the fruit flies’ lifespan by approximately two-thirds. This, you’d figure would be a result of the lack of peaceful, undisturbed sleep that this gene inflicts upon them. However, when removing the insomniac gene from the neurons of the flies, this proved differently. The poor sleep they were able to get still remained, but the lifespan went back to its original length. This breakthrough suggests that sleep may not have to affect the lifespan of an individual. Thus, whichever professors and parents and advisors say we aren’t getting enough sleep may actually be wrong after all. With this knowledge, sleep may possibly not affect overall health at all. We may not be fruit flies, but every animal sleeps, so how far off could the mark really be?