Genetics and how it is linked to sleep deprivation

    The amount of sleep a person gets on average varies for a multitude of reasons. These can be and are not limited to: caffeine intake, sleeping schedules, sleeping patterns, etc. But what you may not have known is that the amount of sleep a person may get is also due to genetics. 

    In every person, there is an internal clock. It is located in the brain and regulates the timing of certain functions. Everyone's internal clock is set to 24 hours, but it may vary. Genes are a factor of how fast or slow this internal clock, also known as circadian rhythms, ticks. Genes control circadian rhythm by encoding "clock proteins." This forms an internal feedback loop in which a cell will produce proteins within a span of 24 hours. The production of rhythm ticks does poorly in light because light indicates that it is daytime which limits the production of melatonin. This is only one example but this shows how genetics can cause the amount of sleep a person may get. 

    If you are a person that lacks sleep, there should be measures taken to allow the production of Circadian rhythm to function properly as eliminating light when you are trying to sleep. 

Links:

https://www.sciencedirect.com/science/article/pii/S0006295221000897

https://sleep.hms.harvard.edu/education-training/public-education/sleep-and-health-education-program/sleep-health-education-80

Schizophrenia: Genes related to circadian rhythms may be disrupted

New research examines the brains of people with schizophrenia and finds disrupted patterns of expression in genes linked with sleep-wake cycles. Prof. McClung and the team obtained postmortem gene expression data from 150 people, 46 of whom had lived with schizophrenia. The people had been younger than 65 years old when they died, and the researchers had access to the times of death. Specifically, the researchers looked at gene expression in the dorsolateral prefrontal cortex, a brain area involved in cognition and memory. In their present study, Prof. McClung and the team examined the rhythms by which some genes switched on and off in the brains of people with schizophrenia and compared these rhythms with those in the brains of people who did not have the condition. Some of these disruptions affected the functioning of mitochondria. When Seney and McClung compared gene expression in brains from people who died during the day, the control and schizophrenia subjects were not different, but in those who died at night, there were major differences, since genes that had gained a rhythm had hit their low point during the night.

https://www.sciencedaily.com/releases/2019/08/190809085738.htm

https://www.medicalnewstoday.com/articles/326017.php#1

Obesity in Mice and Limited Meal Times

Circadian clocks are biochemical oscillators that cycle with a stable phase, synchronized with solar time.  In mice, those who have clocks that do not run correctly, it can be related to obesity and diabetes.  However, scientists have recently discovered that limited meal times for these mice can allow for them to stay healthy and have a lower risk of metabolic diseases.  Scientist Kristen Eckel-Mahan says that these restricted feeding times are very powerful in improving the functions of these mice's clocks.  This is because circadian clocks keep physiological time in almost all of the organs in the body.  The article describes a study to test the feeding times in comparison with circadian clocks in different strains of mice.  One completely without Chryptochrome (clock component) and two who were each missing one of two clock-related genes. Mice that were able to access a high-fat diet at any time of the day were shown to have gained weight, and developed high-cholesterol and insulin problems, while those mice who were limited to the diet within only 10 hours of the day did not develop these problems.  This proves that external timing can take place of the missing internal timing component says scientists of the Salk Institute. This is said to have "translational potential" and may be able to help people with clock mutations that may be linked to metabolic diseases.  Perhaps external factors such as limited eating times can affect those with internal clock mutations in a positive way. 

https://www.the-scientist.com/news-opinion/limited-meal-times-prevent-obesity-in-mice-prone-to-gaining-weight-64734

http://www.pnas.org/content/104/9/3342

Sleep and Genetics

The reason why you can't sleep could be linked to your genetics. There is new research that shows a specific mutation that changes the circadian rhythm of genes that carry it. A person's circadian rhythm is a 24 hour cycle of the physiological processes, which include sleep and wake cycles. However, many people suffer from disrupted sleep patterns, one being delayed sleep phase disorder (DSPD), which is the inability to get to sleep early. DSPD delays hormones, especially in melatonin levels. Also, the hormones necessary to transition into the sleep phase of the cycle is inhibited due to an overactivity of the protein that produces it, that is caused by the mutation in a gene called CRY1.
It was found that most individuals who had the gene mutation had delayed sleep patterns.

More research like this can allow for a greater understanding of disrupted sleep patterns, which can lead to the development of new drugs to combat it.

Article: https://newatlas.com/gene-explains-night-owl-sleep/48902/
Original Study: https://www.sciencedaily.com/releases/2018/03/180309095520.htm

Circadian clock discovery could help boost water efficiency in food plants

          Research scientists at the Texas A&M AgriLife Research Center have discovered how the circadian clock functions in pineapples. In the study, the researchers identified 1,398 transcription factors, proteins that regulate expression of certain genes in pineapples. Half of the transcription factors were discovered to exhibit diurnal gene expression patterns, meaning that their gene expression is regulated by the time-of-day. The researchers now hope to use this information to learn more about how efficiently all plants, namely food plants, regulate water in their systems.    
      Pineapples function by using CAM photosynthesis, meaning that they only open their stomata during the nighttime to minimize water loss. Other plants, like rice, wheat, soybean and cotton, use C3 photosynthesis, which entails opening their stomata in the daytime. C3 photosynthesis is less efficient than CAM photosynthesis because more water evaporates from a plants’ stomata if they are open in the daytime than if they are open at night.
       The researchers also found individual components of the circadian clock that regulates the CAM photosynthetic activity in pineapples. The next step for the scientists is to confirm the functions of the circadian oscillator, with hopes of understanding more about the genetic mechanisms of highly water-efficient CAM photosynthesis. The main goal of this research is to understand CAM photosynthesis and learn how to apply it to C3 plants, allowing them to use both methods of photosynthesis. If food plants can use the CAM pathway to photosynthesize, they will be able to adapt to changing climates more easily, and grow in locations uninhabitable to them today. 
      Since the human population on Earth is constantly growing, more food sources are always needed. If scientists can figure out how to give C3 plants the ability to also photosynthesize using the CAM pathway, the food plants will become more water efficient and will be able to grow in more places, giving humans a larger food supply. Many people go hungry throughout the world, so, I think that this is a great idea; by making food crops like wheat and rice more plentiful, there will be more food to go around, for humans and animals. 

Article : Circadian clock discovery could help boost water efficiency in food plants

For more information on photosynthetic pathways click here

Pineapple genome offers insight into drought-tolerant plants

 

The production of pineapples began in 

southwest Brazil and northeast Paraguay. Pineapples have been cultivated by humans for more than six-thousand years and are now produced in more than eighty-five countries. In a recent study, scientists are homing in on the genes and the genetic pathways which allow the pineapple plant to prosper in environments that are water-limited by sequencing the juicy plant’s genome. Similar to many plants, the ancestors of pineapple and grasses experienced several doublings of their genomes. Although, the analysis shows that unlike the grasses that share an ancestor with pineapple, the pineapple genome has one-less whole genome duplication. This information indicated that pineapple plant is the best comparison group for the study of cereal crop genomes. Overall, the findings provided evidence of two-whole genome duplications in the pineapple plant’s history and a new opening on the evolutionary history of grasses. 

A majority of crop plants make use of a type of photosynthesis called C3. The juicy pineapple plant uses a special type of photosynthesis, called crassulacean acid metabolism, also known as CAM. CAM has evolved in more than ten-thousand plant species independently and the pineapple plant is valued the most economically out of all ten-thousand. Biology professor Ray Ming states “CAM plants use only 20 percent of the water used by typical C3 crop plants, and CAM plants can grow in dry, marginal lands that are unsuited for most crop plants.” By looking more closely at the pineapple genome, it was revealed that some genes which contribute to CAM photosynthesis are actually regulated by the plants circadian clock genes. Circadian clock genes allow plants to distinguish between day and night and alter their metabolism as a result. 

This study allowed scientists to find a link among regulatory elements of CAM photosynthesis genes and the circadian clock regulation for the first time. “CAM photosynthesis allows plants to close the pores in their leaves during the day and open them at night,” states Professor Ming, illustrating how that contributes to the pineapple plant’s resilience in hot climates and that the plant loses very little moisture through its leaves during the course of the day. CAM plants greatly reduce water loss by keeping their stomata closed during the day.

The team involved in this study wrote “All plants contain the necessary genes for CAM photosynthesis and the evolution of CAM simply required rerouting of pre-existing pathways.” The team is responsible for the discovering in which CAM photosynthesis evolved by reconfiguring molecular pathways involved in C3 and CAM photosynthesis. 

Having many farmers within the family and understanding how devastating a drought can be for the crops and overall production for that year, this article was attention-grabbing. The scientists now look to use their understanding of the evolution of the different types of photosynthesis in effort to develop drought-tolerant crops. “Higher water-use efficiency is a highly desirable trait, given the need to double food production by 2050 in the context of a changing climate,” stated Ray Ming. Furthermore, the adaptation of food crops to be more tolerant of a drought will also help humans become accustomed to climate change. 

Original Article