小鼠实验 z-bo 2020-11-25 341

　　Some people always look good, some people yawn constantly; some people wake up after a while, but some people need to "hibernate." This may be genes at work.

　　Recently, scientists conducted research on several families and discovered a new gene that is said to be directly related to the length of sleep required by individuals.

　　"The average person spends 1/3 of their life on sleep, but our understanding of sleep is really lacking. The amazing and groundbreaking thing about this research is that it gives us a glimpse into the brain that determines sleep. And sober many complex circuits and various types of neurons.” said Louis Ptácek, a neuroscientist at the University of California, San Francisco (UCSF).

　　In recent years, there have been many achievements in research on genes related to circadian rhythm, but when it comes to genes that affect sleep (especially genes that regulate the length of sleep required by the body), people know very little.

　　Ptácek and UCSF's geneticist Fu Weihui (transliteration) are both the lead authors of this paper. Their research involves several families, in which several members of one family can sleep only 6 hours a day and still maintain normal physical and mental health . The researchers found the gene ADRB1 that determines the length of sleep after analyzing the DNA of this family. Subsequent genetic linkage studies and whole-exome sequencing revealed a rare mutation in the ADRB1 gene of these members that has not been discovered before.

　　Researchers discovered that this mutant gene encodes β1-adrenergic receptor, and it makes the protein's stability worse, thereby affecting the function of the receptor. In other words, this genetic mutation may have an impact on the level of brain function.

　　Then, the researchers conducted a series of experiments with mice carrying this genetic mutation, and found that the average sleep time of these mice was 55 minutes shorter than that of ordinary mice (humans carrying the mutation sleep two hours less). Further analysis showed that the expression level of this gene is very high on the dorsal side of the mouse pons (part of the brainstem), and this region is responsible for unconscious functions such as breathing, eye movement, and sleep.

　　Researchers also found that neurons in this area with the normal ADRB1 gene are not only more active in the waking state, but also more active in the rapid eye movement (REM) sleep period, and are only static in the non-REM period. Neurons carrying mutant genes are more active than normal neurons, which may lead to shorter sleep time.

　　However, Ptácek admits that there are some limitations in using mice to study sleep behavior. For example, the sleep patterns of mice are different from those of humans, and their sleep time is fragmented, instead of sleeping in a continuous period like humans. In future research, the two scientists also plan to further explore the function of ADRB1 protein in other parts of the brain, and to find other important genes that may be related in more families.