• 제목/요약/키워드: Biological adaptation

검색결과 198건 처리시간 0.035초

Molecular adaptation of the CREB-Binding Protein for aquatic living in cetaceans

  • Jeong, Jae-Yeon;Chung, Ok Sung;Ko, Young-Joon;Lee, Kyeong Won;Cho, Yun Sung;Bhak, Jong;Yim, Hyung-Soon;Lee, Jung-Hyun
    • 한국해양바이오학회지
    • /
    • 제6권2호
    • /
    • pp.102-109
    • /
    • 2014
  • Cetaceans (whales, dolphins, and porpoises) are aquatic mammals that experienced drastic changes during the transition from terrestrial to aquatic environment. Morphological changes include streamlined body, alterations in the face, transformation of the forelimbs into flippers, disappearance of the hindlimbs and the acquisition of flukes on the tail. For a prolonged diving, cetaceans acquired hypoxia-resistance by developing various anatomical and physiological changes. However, molecular mechanisms underlying these adaptations are still limited. CREB-binding protein (CREBBP) is a transcriptional co-activator critical for embryonic development, growth control, metabolic homeostasis and responses to hypoxia. Natural selection analysis of five cetacean CREBBPs compared with those from 15 terrestrial relatives revealed strong purifying selection, supporting the importance of its role in mammals. However, prediction for amino acid changes that elicit functional difference of CREBBP identified three cetacean specific changes localized within a region required for interaction with SRCAP and in proximal regions to KIX domain of CREBBP. Mutations in CREBBP or SRCAP are known to cause craniofacial and skeletal defects in human, and KIX domain of CREBBP serves as a docking site for transcription factors including c-Myb, an essential regulator of haematopoiesis. In these respects, our study provides interesting insights into the functional adaptation of cetacean CREBBP for aquatic lifestyle.

Mitochondrial OXPHOS genes provides insights into genetics basis of hypoxia adaptation in anchialine cave shrimps

  • Guo, Huayun;Yang, Hao;Tao, Yitao;Tang, Dan;Wu, Qiong;Wang, Zhengfei;Tang, Boping
    • Genes and Genomics
    • /
    • 제40권11호
    • /
    • pp.1169-1180
    • /
    • 2018
  • Cave shrimps from the genera Typhlatya, Stygiocaris and Typhlopatsa (TST complex) comprises twenty cave-adapted taxa, which mainly occur in the anchialine environment. Anchialine habitats may undergo drastic environmental fluctuations, including spatial and temporal changes in salinity, temperature, and dissolved oxygen content. Previous studies of crustaceans from anchialine caves suggest that they have possessed morphological, behavioral, and physiological adaptations to cope with the extreme conditions, similar to other cave-dwelling crustaceans. However, the genetic basis has not been thoroughly explored in crustaceans from anchialine habitats, which can experience hypoxic regimes. To test whether the TST shrimp-complex hypoxia adaptations matched adaptive evolution of mitochondrial OXPHOS genes. The 13 OXPHOS genes from mitochondrial genomes of 98 shrimps and 1 outgroup were examined. For each of these genes was investigated and compared to orthologous sequences using both gene (i.e. branch-site and Datamonkey) and protein (i.e. TreeSAAP) level approaches. Positive selection was detected in 11 of the 13 candidate genes, and the radical amino acid changes sites scattered throughout the entire TST complex phylogeny. Additionally, a series of parallel/convergent amino acid substitutions were identified in mitochondrial OXPHOS genes of TST complex shrimps, which reflect functional convergence or similar genetic mechanisms of cave adaptation. The extensive occurrence of positive selection is suggestive of their essential role in adaptation to hypoxic anchialine environment, and further implying that TST complex shrimps might have acquired a finely capacity for energy metabolism. These results provided some new insights into the genetic basis of anchialine hypoxia adaptation.

Bioconversion of Linoleic Acid to Conjugated Linoleic Acid by Bifidobacterium breve

  • Song Yoon-Seok;Kang Seong-Woo;Oh Deok-kun;Rho Yong-Taik;Hong Suk-In;Kim Seung-Wook
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • 제10권4호
    • /
    • pp.357-361
    • /
    • 2005
  • The bioconversion of linoleic acid (LA) to conjugated linoleic acid (CLA) was investigated to examine LA-adaptation of Bifidobacterium breve KCTC 3461 to additions of 1 to 5 mg/mL of LA overtime. To induce LA-adaptation, B. breve KCTC 3461 was treated with LA, according to three schemes. For LA-adapted B. breve the maximum concentration of CLA, $300\~350{\mu}g/mL$, was obtained in cys-MRS medium containing 1 mg/mL of LA. The CLA production significantly increased with increasing LA concentration, from 1 to 4 mg/mL, but the conversion of LA to CLA gradually decreased. The CLA production capability of B. breve, and its tolerance, improved significantly with LA-adaptation. The addition of LA (1 mg/mL) into the culture broth after 24 h of cultivation in a 100-mL media bottle was most effective at promoting CLA production. In a 2.5-L stirred-tank bioreactor, the observed conversion and productivity of $56.6\%\;and\;35.4{\mu}gmL^{-1}h^{-1}$, respectively, by LA-adapted B. breve were approximately 6.6 and 9.8 times higher than those of LA-unadapted B. breve.

고혈압환자의 폭염 적응력 증진을 위한 프로그램 효과 (Effects of an Extreme Heat Adaptation Program in Hypertensive Patients)

  • 정성희;김남순;채수미;이은주
    • Journal of Korean Biological Nursing Science
    • /
    • 제16권3호
    • /
    • pp.164-172
    • /
    • 2014
  • Purpose: The purpose of this study was to identify the effects of an extreme heat Adaptation Program on the blood pressure, stress response, self-efficacy, and knowledge of management of hypertension and extreme heat of patients who suffered from hypertension. Methods: A quasi-experimental study with a non-equivalent control group pretest-posttest design was used. The data collection period was between July 2 and August 20, 2012. Thirty-seven patients participated in the study (18 in the experimental group and 19 in the control group). Data were analyzed using $X^2$-test, t-test, and Cronbach's alpha coefficients with SPSS/WIN 19.0. Results: Patients who participated in the program showed statistically significant improvements in systolic blood pressure (SBP), self-efficacy, and knowledge of management of hypertension and extreme heat. Conclusion: The results indicate that this extreme heat adaptation program can be utilized for patients suffering from hypertension in order to reduce their SBP and to increase self-efficacy and knowledge of management of hypertension and extreme heat. Therefore, it is recommended that this program be used for elderly patients suffering from chronic disease.

인공와우 어음처리방식을 위한 적응효과 알고리즘의 음성개시점 검출 특성 비교 (Comparison of Speech Onset Detection Characteristics of Adaptation Algorithms for Cochlear Implant Speech Processor)

  • 최성진;김진호;김경환
    • 대한의용생체공학회:의공학회지
    • /
    • 제29권1호
    • /
    • pp.25-31
    • /
    • 2008
  • It is well known that temporal information, i.e speech onset, about input speech can be represented to the response nerve signal of auditory nerve better depending on the adaptation effect occurred in the auditory nerve synapse. In addition, the performance of a speech processor of cochlear implant can be improved by the adaptation effect. In this paper, we observed the emphasis characteristic of speech onset in the recently proposed adaptation algorithm, analyzed the characteristic of performance change according to the variation of parameters and compared with transient emphasis spectral maxima (TESM) is the previous typical strategy. When observing false peaks which are generated everywhere except speech onset, in the case of the proposed model, the false peak were generated much less than in the case of the TESM and it is more distinguishable under noise.

Biochemical Adaptation to the Freezing Environment - the Biology of Fish Antifreeze Proteins

  • Li, Zhengjun;Li, n Qingsong;Low Woon-Kai;Miao Megan;Hew Choy L.
    • Ocean and Polar Research
    • /
    • 제25권4호
    • /
    • pp.607-615
    • /
    • 2003
  • Many organisms are known to survive in icy environments. These include both over wintering terrestrial insects and plants as well the marine fish inhabiting high latitudes. The adaptation of these organisms is both a fascinating and important topic in biology. Marine teleosts in particular, can encounter ice-laden seawater that is approximately $1^{\circ}C$ colder than the colligative freezing point of their body fluids. These animals produce a unique group of proteins, the antifreeze proteins (AFPs) or antifreeze glycoproteins (AFGPs) that absorb the ice nuclei and prevent ice crystal growth. Presently, there are at least four different AFP types and one AFGP type that are isolated from a wide variety of fish. Despite their functional similarity, there is no apparent common protein homology or ice-binding motifs among these proteins, except that the surface-surface complementarity between the protein and ice are important for binding. The remarkable diversity of these proteins and their odd phylogenetic distribution would suggest that these proteins might have evolved recently in response to sea level glaciations just 1-2 million years ago in the northern hemisphere and 10-30 million years ago around Antarctica. Winter flounder, Pleuronectes americanus, has been used as a popular model to study the regulation of AFP gene expression. It has a built-in annual cycle of AFP expression controlled negatively by the growth hormone. The signal transduction pathways, transcription factors and promoter elements involved in this process have been studied in our laboratory and these studies will be presented.

콘텐츠 적응화 서비스를 위한 상황정보 수집 시스템의 설계 및 구현 (A Design and Implementation of Context Information Gathering System for Contents Adaptation Service)

  • 전우락;소수환;이재동
    • 한국산업정보학회논문지
    • /
    • 제14권2호
    • /
    • pp.1-7
    • /
    • 2009
  • 본 논문은 센서로부터 사용자의 환경정보를 수집하여 상황정보 프로파일을 생성히는 시스템을 제안한다. 본 논문에서는 유비쿼터스 컴퓨팅 환경에서의 상황인지에 대한 연구결과를 바탕으로 상황을 분류하고, 상황정보를 모델링하였다. 제안된 시스템은 다양한 일상생활에서 사용자에게 발생할 수 있는 주변환경 정보 및 신체정보를 수집하여, 상황정보 프로파일을 생성함으로써 콘텐츠 적응화 서비스를 지원할 수 있다.

Rice genotype, parental lineage and physiological tolerance to soil salinity shapes the community structure of rice seed bacterial endophytes

  • Walitang, Denver I.;Kim, Kiyoon;Chatterjee, Poulami;Kang, Yeongyeong;Sa, Tongmin
    • 한국작물학회:학술대회논문집
    • /
    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
    • /
    • pp.342-342
    • /
    • 2017
  • Rice seeds are a home to endophytic bacterial communities which serve as a source of the plant's endophytes. As rice undergo physiological and adaptive modifications through cross breeding in the process of attaining salinity tolerance, this may also lead to changes in the endophytic bacterial community especially those residing in the seeds. This study explores the community structure of seed bacterial endophytes as influenced by rice parental lineage, genotype and physiological adaptation to salinity stress. Endophytic bacterial diversity was studied through culture dependent technique, cloning and Terminal-Restriction Fragment Length Polymorphism (T-RFLP) analysis. Results revealed considerably diverse communities of bacterial endophytes in the interior of rice seeds. The richness of ribotypes ranges from 5-14 T-RFs corresponding to major groups of bacterial endophytes in the seeds. Endophytic bacterial diversity of the salt-sensitive IR29 is significantly more diverse compared to those of salt-tolerant cultivars. Proteobacteria followed by Actinobacteria and Firmicutes dominated the overall endophytic bacterial communities of the indica rice seeds based on 16S rDNA analysis of clones and isolates. Community profiles show common ribotypes found in all cultivars of the indica subspecies representing potential core microbiota belonging to Curtobacterium, Flavobacterium, Enterobacter, Xanthomonas, Herbaspirillum, Microbacterium and Stenotrophomonas. Multivariate analysis showed that the bacterial endophytic community and diversity of rice seeds are mainly influenced by their host's genotype, physiological adaptation to salt stress and parental lineage.

  • PDF