scholarly journals DNA in Motion

2021 ◽  
Vol 83 (7) ◽  
pp. 458-463
Author(s):  
David A. Johnson
Keyword(s):  
Dna Structure ◽  
Base Pairs ◽  
Single Nucleotide ◽  
Chemical Concepts ◽  
Active Modeling ◽  
Functional Features ◽  
Leading Strand ◽  
Simple Activity ◽  
Active Processes ◽  
And Function

Students often struggle to understand the full implications of some basic chemical concepts of DNA structure and function, especially how DNA’s directionality and antiparallel nature determine key functional features of replication and molecular recombination. Visualizing the complexities of these processes requires a working knowledge of how DNA’s nucleotides are assembled and how these components interact. This article describes a simple activity that can be used to visualize how nucleotides join together, how base pairs form, and, most importantly, how the active processes of replication and recombination are related to DNA chemistry. In this activity, students model DNA structure, with each student representing a single nucleotide, then join together to form a polynucleotide with 5′ to 3′ directionality. Two chains then pair to form the antiparallel DNA duplex. The activity not only illustrates the basic chemistry of DNA but also allows students to participate in active modeling of leading-strand and lagging-strand replication and in the formation of the Holliday junction molecule, the basic intermediate of recombination events including crossing over and gene conversion. The demonstrations can be videotaped from above to make a permanent copy of these events for teaching and study purposes. Example illustrations and links to videos are included.

scholarly journals Intrinsic disorder in protein domains contributes to both organism complexity and clade-specific functions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chao Gao ◽  
Chong Ma ◽  
Huqiang Wang ◽  
Haolin Zhong ◽  
Jiayin Zang ◽  
...  
Keyword(s):  
Biological Significance ◽  
Protein Domains ◽  
Functional Requirements ◽  
Post Translational Modification ◽  
Intrinsically Disordered ◽  
Genome Wide ◽  
Complex Functions ◽  
Disorder Degree ◽  
Functional Features ◽  
And Function

AbstractInterestingly, some protein domains are intrinsically disordered (abbreviated as IDD), and the disorder degree of same domains may differ in different contexts. However, the evolutionary causes and biological significance of these phenomena are unclear. Here, we address these issues by genome-wide analyses of the evolutionary and functional features of IDDs in 1,870 species across the three superkingdoms. As the result, there is a significant positive correlation between the proportion of IDDs and organism complexity with some interesting exceptions. These phenomena may be due to the high disorder of clade-specific domains and the different disorder degrees of the domains shared in different clades. The functions of IDDs are clade-specific and the higher proportion of post-translational modification sites may contribute to their complex functions. Compared with metazoans, fungi have more IDDs with a consecutive disorder region but a low disorder ratio, which reflects their different functional requirements. As for disorder variation, it’s greater for domains among different proteins than those within the same proteins. Some clade-specific ‘no-variation’ or ‘high-variation’ domains are involved in clade-specific functions. In sum, intrinsic domain disorder is related to both the organism complexity and clade-specific functions. These results deepen the understanding of the evolution and function of IDDs.

In Silico Identification of Novel Acute Myeloid Leukemia Associated Missense SNPs in Human CEBPA Gene

2020 ◽  
pp. 10-24
Keyword(s):  
Acute Myeloid Leukemia ◽  
In Silico ◽  
Myeloid Leukemia ◽  
Gene Interaction ◽  
Nucleotide Polymorphisms ◽  
Future Perspectives ◽  
Single Nucleotide ◽  
In Silico Identification ◽  
And Function ◽  
Acute Myeloid

Single nucleotide polymorphisms (SNPs) in CEBPA gene have been found to be associated with cancer especially Acute Myeloid Leukemia (AML). Therefore, the identification of functional and structural polymorphisms in CEBPA is important to study and discover therapeutics targets and potential malfunctioning. For this purpose, several bioinformatics tools were used for the identification of disease-associated nsSNPs, which might be vital for the structure and function of CEBPA, making them extremely important. In silico tools used in this study included SIFT, PROVEAN, PolyPhen2, SNP&GO and PhD-SNP, followed by ConSurf and I-Mutant. Protein 3D modelling was carried out using I-TASSER and MODELLER v9.22, while GeneMANIA and string were used for the prediction of gene-gene interaction in this regard. From our study, we found that the L345P, R333C, R339Q, V328G, R327W, L317Q, N292S, E284A, R156W, Y108N and F82L mutations were the most crucial SNPs. Additionally, the gene-gene interaction showed the genes having correlation with CEBPA’s co-expressions and importance in several pathways. In future, these 11 mutations should be investigated while studying diseases related to CEBPA, especially for AML. Being the first of its kind, future perspectives are proposed in this study, which will help in precision medicine. Animal models are of great significance in finding out CEBPA effects in disease.

Genes Regulating Immune Response and Amelogenesis Interact in Increasing the Susceptibility to Molar-Incisor Hypomineralization

2018 ◽  
Vol 53 (2) ◽  
pp. 217-227 ◽  
Author(s):  
Diego Girotto Bussaneli ◽  
Manuel Restrepo ◽  
Camila Maria Bullio Fragelli ◽  
Lourdes Santos-Pinto ◽  
Fabiano Jeremias ◽  
...  
Keyword(s):  
Immune Response ◽  
Gene Interactions ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Nuclear Families ◽  
Molar Incisor Hypomineralization ◽  
Inflammatory Stimuli ◽  
Allele Specific ◽  
Family Based ◽  
And Function

Ameloblasts are sensitive cells whose metabolism and function may be affected by inflammatory stimuli. The aim of this study was to evaluate the possible association between polymorphisms in immune response-related genes and molar-incisor hypomineralization (MIH), and their interaction with polymorphisms in amelogenesis-related genes. DNA samples were obtained from 101 nuclear families that had at least 1 MIH-affected child. Eleven single-nucleotide polymorphisms (SNPs) were investigated in immune response genes using TaqMan® technology allele-specific probes. A transmission disequilibrium test was performed to verify overtransmission of alleles in all MIH families, as well as in families only with mild or severe MIH-affected children. Gene-gene interactions between the immune-related and amelogenesis-related polymorphisms were analyzed by determining whether alleles of those genes were transmitted from heterozygous parents more often in association than individually with MIH-affected children. In severe cases of MIH, significant results were observed for rs10733708 (TGFBR1, OR = 3.5, 95% CI = 1.1–10.6). Statistical evidence for gene-gene interactions between rs6654939 (AMELX) and the SNPs rs2070874 (IL4), rs2275913 (IL17A), rs1800872 (IL10), rs1800587 (IL1A), and rs3771300 (STAT1) was observed. The rs2070874 SNP (IL4) was also significantly overtransmitted from heterozygous parents with the rs7526319 (TUFT1) and the rs2355767 (BMP2) SNPs, suggesting a synergistic effect of the transmission of these alleles with susceptibility to MIH. This family-based study demonstrated an association between variation in TGFBR1 and MIH. Moreover, the polymorphisms in immune response and amelogenesis genes may have an additive effect on the risk of developing MIH.

scholarly journals Oligonucleotides DNA containing 8-trifluoromethyl-2′-deoxyguanosine for observing Z-DNA structure

2020 ◽  
Author(s):  
Hong-Liang Bao ◽  
Tatsuki Masuzawa ◽  
Takanori Oyoshi ◽  
Yan Xu
Keyword(s):  
Genetic Diseases ◽  
Dna Structure ◽  
2D Nmr ◽  
Living Cells ◽  
Molecular Probes ◽  
Alternative Form ◽  
Left Handed ◽  
Z Dna ◽  
And Function

Abstract Z-DNA is known to be a left-handed alternative form of DNA and has important biological roles as well as being related to cancer and other genetic diseases. It is therefore important to investigate Z-DNA structure and related biological events in living cells. However, the development of molecular probes for the observation of Z-DNA structures inside living cells has not yet been realized. Here, we have succeeded in developing site-specific trifluoromethyl oligonucleotide DNA by incorporation of 8-trifluoromethyl-2′-deoxyguanosine (FG). 2D NMR strongly suggested that FG adopted a syn conformation. Trifluoromethyl oligonucleotides dramatically stabilized Z-DNA, even under physiological salt concentrations. Furthermore, the trifluoromethyl DNA can be used to directly observe Z-form DNA structure and interaction of DNA with proteins in vitro, as well as in living human cells by19F NMR spectroscopy for the first time. These results provide valuable information to allow understanding of the structure and function of Z-DNA.

scholarly journals hPSC-Derived Enteric Ganglioids Model Human ENS Development and Function

2022 ◽  
Author(s):  
Homa Majd ◽  
Ryan M Samuel ◽  
Jonathan T Ramirez ◽  
Ali Kalantari ◽  
Kevin Barber ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Xenograft Model ◽  
Developmental Relationships ◽  
Drug Candidates ◽  
Effective Strategies ◽  
Wide Range ◽  
Functional Features ◽  
And Function

The enteric nervous system (ENS) plays a central role in gut physiology and mediating the crosstalk between the gastrointestinal (GI) tract and other organs. The human ENS has remained elusive, highlighting the need for an in vitro modeling and mapping blueprint. Here we map out the developmental and functional features of the human ENS, by establishing robust and scalable 2D ENS cultures and 3D enteric ganglioids from human pluripotent stem cells (hPSCs). These models recapitulate the remarkable neuronal and glial diversity found in primary tissue and enable comprehensive molecular analyses that uncover functional and developmental relationships within these lineages. As a salient example of the power of this system, we performed in-depth characterization of enteric nitrergic neurons (NO neurons) which are implicated in a wide range of GI motility disorders. We conducted an unbiased screen and identified drug candidates that modulate the activity of NO neurons and demonstrated their potential in promoting motility in mouse colonic tissue ex vivo. We established a high-throughput strategy to define the developmental programs involved in NO neuron specification and discovered that PDGFR inhibition boosts the induction of NO neurons in enteric ganglioids. Transplantation of these ganglioids in the colon of NO neuron-deficient mice results in extensive tissue engraftment, providing a xenograft model for the study of human ENS in vivo and the development of cell-based therapies for neurodegenerative GI disorders. These studies provide a framework for deciphering fundamental features of the human ENS and designing effective strategies to treat enteric neuropathies.  

scholarly journals Candidate genes associated with athletes' skeletal muscle functions regulation

2021 ◽  
Vol 1 (2) ◽  
pp. 83-94
Author(s):  
O. V. Balberova ◽  
E. V. Bykov ◽  
G. V. Medvedev
Keyword(s):  
Candidate Genes ◽  
Skeletal Muscles ◽  
Sports Injuries ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Genetic Characteristics ◽  
Endurance Strength ◽  
Personalized Approach ◽  
And Function ◽  
Genetically Determined

It is generally recognized that an elite athlete's status is a multifactorial phenotype depending on many environmental and genetic factors. Variations in the sequence of nucleotides in deoxyribonucleic acid (DNA), in particular, single-nucleotide variants (SNVs) act as key internal factors associated with achieving high results in sports. The determination of specific individuals' genetic characteristics allows us to identify athletes who have the greatest genetically determined potential for certain sports that require speed, strength or endurance manifestation. Of course, peculiarities of the structure and function of skeletal muscles are among the most important characteristics in sports results context, in sports associated with the development of power / strength or endurance phenotypes. The composition and function of skeletal muscles are controlled by many different genes, and their SNVs can serve as strength or endurance athletes' status biomarkers. (1) Background: to conduct a thematic review of candidate genes studies and their single-nucleotide variants (SNVs) associated with the functioning of skeletal muscles in athletes. (2) Methods: A search for articles for the period from 2010 to 2020 was conducted in the databases SCOPUS, Web of Science, Google Calendar, Clinical keys, PubMed, e-LIBRARY using keywords and their combinations; (3) Conclusions: The identification of genetic biomarkers associated with muscular system regulation can help neurologists, sports doctors and coaches in developing personalized strategies for selecting children, adolescents and young adults for endurance, strength and speed sports (for example, running short, medium or long distances). Such a personalized approach will increase sports performance and reduce the risk of sports injuries of the musculoskeletal system.

Timing during translation matters: synonymous mutations in human pathologies influence protein folding and function

2018 ◽  
Vol 46 (4) ◽  
pp. 937-944 ◽  
Author(s):  
Robert Rauscher ◽  
Zoya Ignatova
Keyword(s):  
Protein Folding ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide ◽  
Synonymous Mutations ◽  
Translation Velocity ◽  
Disease Penetrance ◽  
And Function ◽  
Related Proteins ◽  
Translational Speed ◽  
Fine Tune

Ribosomes translate mRNAs with non-uniform speed. Translation velocity patterns are a conserved feature of mRNA and have evolved to fine-tune protein folding, expression and function. Synonymous single-nucleotide polymorphisms (sSNPs) that alter programmed translational speed affect expression and function of the encoded protein. Synergistic advances in next-generation sequencing have led to the identification of sSNPs associated with disease penetrance. Here, we draw on studies with disease-related proteins to enhance our understanding of mechanistic contributions of sSNPs to functional alterations of the encoded protein. We emphasize the importance of identification of sSNPs along with disease-causing mutations to understand genotype–phenotype relationships.

Basic principles of genetic disease

ESC CardioMed ◽  
2018 ◽  
pp. 669-671
Author(s):  
Eric Schulze-Bahr
Keyword(s):  
Genetic Disease ◽  
Copy Number ◽  
Copy Number Variants ◽  
Single Nucleotide Variants ◽  
Individual Genome ◽  
Base Pairs ◽  
Single Nucleotide ◽  
Basic Principles ◽  
Bona Fide ◽  
Genomic Regions

The human genome consists of approximately 3 billion (3 × 109) base pairs of DNA (around 20,000 genes), organized as 23 chromosomes (diploid parental set), and a small mitochondrial genome (37 genes, including 13 proteins; 16,589 base pairs) of maternal origin. Most human genetic variation is natural, that is, common or rare (minor allele frequency >0.1%) and does not cause disease—apart from every true disease-causing (bona fide) mutation each individual genome harbours more than 3.5 million single nucleotide variants (including >10,000 non-synonymous changes causing amino acid substitutions) and 200–300 large structural or copy number variants (insertions/deletions, up to several thousands of base-pairs) that are non-disease-causing variations and scattered throughout coding and non-coding genomic regions.

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