Gansu Zokor Hypoxia Adaptation And Acth, Blood Physiological Indexes And Hemoglobin Alpha Globin Gene Research

Gansu zokor(myospalax cansus),a harmful gnawer in the northwest loess plateau of our country, whose life lived in the underground and is typical of the environment of low oxygen and high carbon dioxide which lead to come into many special mechanisms to fit the environment, is an excellent model animal to study to adapt to low oxygen and high carbon dioxide environment. At present, about Gansu zokor hypoxia adaptation and corticotropin (adrenocorticotropic hormone, ACTH), blood physiological parameters and hemoglobin alpha-globin gene relationship between research have not been reported.To measure the effects of hypoxia on adrenocorticotropic hormone (ACTH) and blood parameters in Gansu Zokor(Myospalax cansus). The number of red blood cell (RBC), hemoglobin concentration (HGB), hematocrit (HCT), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) contents in Gansu Zokor were measured with Sysmex KX-21N hematology analyzer, the adrenocorticotropic hormone (ACTH) contents were measured with SN-695A RIA y measuring instrument before and after hypoxia. The use of molecular biology method of clone the determination Gansu zokor hemoglobin alpha-globin gene sequences, in order to be able to provide some basis for the study of the Gansu zokor physiological and molecular adaptation mechanism.The results showed that:After myospalax cansus had adapted to the low oxygen conditions HGB significantly increased, and the higher low oxygen degree was, the more HGB increased. When the oxygen concentration was14.1%,10.5%and6.5%, HGB was significantly higher(p<0.01) than the control group, and the14.1%group was significantly lower(p<0.05) than the6.5%group. RBC and HCT also uninterruptedly increased with the oxygen concentration decrease. The different oxygen concentration group was significantly different compared with the control group. There was significant difference(p<0.05) between the14.1%group and the10.5%group and there was significant difference(p<0.01) between the14.1%group and the6.5%group on RBC and HCT. MCV increased at the14.1%and10.5%oxygen concentration, and slightly decreased at the26.5%oxygen concentration, but there was no significant difference between different groups. MCH and MCHC decreased with the oxygen concentration reduction. There was no significant difference between remaining groups but there was significant difference between the6.5%oxygen concentration and the control group on MCH. There was significant difference(p<0.01) between the control group and the14.1%,10.5%and6.5%oxygen concentration and between the10.5%and6.5%oxygen concentration and there was significant difference(p<0.05) between the14.1%and the6.5%oxygen concentration on MCHC.2After myospalax cansus had adapted to the low oxygen conditions ACTH concentration of the serum significantly increased which was significantly higher(p<0.01) than the control group and the higher low oxygen degree was, the more ACTH increased. ACTH was injected into the abdominal cavity of myospalax cansus, RBC, HGB and HCT significantly increased (p<0.01) compared with the control group, MCV slightly increased, but not significantly and MCH and MCHC decreased compared with the control group but there was no significant difference on MCH and there was significant difference(p<0.01) on MCHC.3After ACTH was injected blood indexs of the control myospalax cansus group including HGB, RBC, HCT, MCV,MCHC and so on were compared with the14.1%,10.5%and6.5%low oxygen groups. There was significant difference(p<0.05) between ACTH group and the26.5%oxygen concentration group on HGB and RBC and between ACTH group and the14.1%and10.5%oxygen concentration group on MCHC. There was no significant difference(p<0.05) between the remaining groups. These results suggest that hypoxia activated hypothalamus-Pituitary-Adrenal (HPA) and increased ACTH contents in serum, further increased corticosterone (CORT), resulting in higher RBC, HGB, and HCT,in order to improve the oxygen carrying capacity of blood and adaptation to hypoxia in Gansu Zokor.In the experiment the aglobin gene orders of myospalax baileyi, peromyscus maniculatus, ochotona cuzniae, rattus norvegicus and mus musculus were found out and compared with each other. The common regions or conservation regions were used to designed to the primers which were used to amplify the myospalax cansus hemoglobinaglobin gene. Three pairs of primers could amplify the right gene segments.463bp gene segment was amplified by the primer one,162bp gene segment by the primer two and435bp gene segment by the primer three. The amplified results of three pairs of primers were compared and spliced by software and a788bp fragments was got. After the products were cloned and sequenced, the results were carried out the homology analysis and myospalax cansus hemoglobinaglobin gene sequence was found. The results of splicing were analyzed by the software. It was inferred that myospalax cansus hemoglobinaglobin gene sequence consisted of140amino acids and contained3exons and2introns.After myospalax cansus hemoglobinaglobin gene sequence was cloned and sequenced, some amino acid sites replacement were found in it. By comparing myospalax cansus and human achain amino acid sequence21amino acids changing were found. In all the replacement sites, the site that α111Ala was replaced by Asn was a key area because the site right located on the hemoglobinα1β1junction. When the human hemoglobin formed, α111site andβ115site were key amino acid residue sites connectingα1β1. Because when the human Hba4degree conformation changed, the relative position of the junction site of α111site andβ115site in theα1β1chain did not change. On myospalax cansus, amino acid replacement happened onα111site anda90site which possibly made the hydrogen bond between α1β1andα1β2disjoint and further induced4degree conformation of hemoglobin hydrogen bond to change which could affect the affinity power between Hb and the oxygen. Compare Gansu zokor, people Plateau Zokor, deer mice, the plateau pika,, mice,, rats and the Israeli blind mole α-bead protein amino acid sequence found in people, plateau pikas, mouse, house mouse α35are amino acid replacement and plateau pika is Leu,â†'Cys, Alaâ†'Cys, in mice and rats, the Gansu zokor35points of amino acids replaced with Cys. Leu, Ala, belonging to the a-amino acid sideacyclic chain of Cys sulfur-containing amino acids of Gansu zokor Cys replacement may increase the hemoglobin oxygen affinity, because the α35for α1β1binding sites, Cys, side-chain disulfide bonds may change the alpha-globinthe gap between the other subunits, making the hemoglobin of the four institutions like the changes, more stable, and further increase the oxygen affinity of hemoglobin.The Gansu zokor Asn72to its unique amino acid, Alaâ†'Asn, people, deer mice, in the plateau pika, Mus musculus by of Aspâ†'Asn, in mice, blind mole of Glyâ†'Asn, Asn,replacement may increase the hemoglobin oxygen affinity the Gansu zokor114Tyr its unique amino acidâ†'of Tyr by Leu, in person, deer mice, in the plateau pika, mice, rats and blind mole by Hisâ†'Tyr, Tyr substitution may increase the hemoglobin oxygen affinity, but whether it will raise from the simulation established Gansu zokor hemoglobin three-dimensional structure, and further clarified. The Gansu zokor point amino acid change has little effect on the hemoglobin does not change its oxygen affinity.Figure seen by the genetic distance of the Gansu zokor a-globin. the distance of Gansu zokor and Plateau Zokor is a minimum of0.0113,followed by the deer mouse distance0.0939, is similar to mice and deer mice from0.104, the distance of Gansu zokor and mice and plateau pika genetic distance is similar,0.1786and0.1840, respectively, with human genetic distance as far as0.2048, the results show higher homology of Gansu zokor and plateau zokor,lower homology of Gansu zokor and human.ClustalX, MEGA3.1and other biological information analysis software Gansu zokor, plateau zokor, plateau pikas, deer mouse, mouse, house mouse and human coding nucleotide sequence phylogenetic tree was constructed. Gansu zokor and plateau zokor is a branch of the results can be seen, and the plateau zokor evolutionary relationship, and human evolutionary relationship between the farthest; norvegicus and mice clustered into a class with deer mice on the same level clustering, then this category of Gansu zokor and plateau zokor, poly into the meet; plateau pika with people clustered together, the two evolutionary relationship closer.α35, α111in Plateau Zokor, amino acid changes in comparison with the people of Gansu zokor of Plateau Zokor amino acid substitution sites are Leu,â†'Cys, Alaâ†'Asn, plateau zokor, and Gansu zokor the case ofunderground rodents, living environment of hypoxia and hypercapnia with this locus in two subterranean rodents, the same change in improve makes of Gansu zokor plateau zokor hemoglobin oxygen affinity. Hemoglobin alpha-globin gene sequence changes the amino acids corresponding change the Gansu zokor a-globin primary structure mutation makes the subunit conformation change, the subunit conformational change makes the hemoglobin molecule’s overall conformation change, and ultimately change the affinity of hemoglobin with oxygen, its affinity to increase. Are of Gansu zokor plateau zokor sites changes illustrate the α35, α111to adapt to the hypoxic sites, changes in this locus one of the hemoglobin molecule mechanism is the Gansu zokor hypoxic adaptation.In this study, determination of Gansu zokor alpha-globin gene sequences and deduced amino acid sequence from the gene sequences to compare differences in amino acid sequence with several other species of a-globin gene, Gansu zokor alpha-globin gene nucleotide sequence is explainedits high hemoglobin content and high oxygen affinity, indicating Gansu zokor alpha-globin genetic differences may be one of the pairs harsh underground hypoxic adaptation of the mechanism.