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2.
J Biosci ; 44(2)2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31180051

RESUMO

Restriction enzymes have been identified in the early 1950s of the past century and have quickly become key players in the molecular biology of DNA. Forty years ago, the scientists whose pioneering work had explored the activity and sequence specificity of these enzymes, contributing to the definition of their enormous potential as tools for DNA characterization, mapping and manipulation, were awarded the Nobel Prize. In this short review, we celebrate the history of these enzymes in the light of their many different uses, as these proteins have accompanied the history of DNA for over 50 years representing active witnesses of major steps in the field.


Assuntos
Mapeamento Cromossômico/história , Clonagem Molecular/métodos , Enzimas de Restrição do DNA/história , DNA/história , Biologia Molecular/história , Mapeamento de Nucleotídeos/história , Sistemas CRISPR-Cas , Cromatina/química , Cromatina/metabolismo , Mapeamento Cromossômico/métodos , DNA/química , DNA/genética , DNA/metabolismo , Metilação de DNA , Enzimas de Restrição do DNA/genética , Enzimas de Restrição do DNA/metabolismo , História do Século XX , História do Século XXI , Humanos , Biologia Molecular/métodos , Prêmio Nobel , Mapeamento de Nucleotídeos/métodos , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/genética , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/história , Nucleases dos Efetores Semelhantes a Ativadores de Transcrição/metabolismo
3.
Nat Rev Genet ; 20(5): 283-297, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30886348

RESUMO

Sophisticated gene-regulatory mechanisms probably evolved in prokaryotes billions of years before the emergence of modern eukaryotes, which inherited the same basic enzymatic machineries. However, the epigenomic landscapes of eukaryotes are dominated by nucleosomes, which have acquired roles in genome packaging, mitotic condensation and silencing parasitic genomic elements. Although the molecular mechanisms by which nucleosomes are displaced and modified have been described, just how transcription factors, histone variants and modifications and chromatin regulators act on nucleosomes to regulate transcription is the subject of considerable ongoing study. We explore the extent to which these transcriptional regulatory components function in the context of the evolutionarily ancient role of chromatin as a barrier to processes acting on DNA and how chromatin proteins have diversified to carry out evolutionarily recent functions that accompanied the emergence of differentiation and development in multicellular eukaryotes.


Assuntos
Montagem e Desmontagem da Cromatina , DNA/genética , Genoma , Nucleossomos/genética , Transcrição Genética , Animais , Evolução Biológica , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/história , Proteínas Cromossômicas não Histona/metabolismo , DNA/história , DNA/metabolismo , Células Eucarióticas/citologia , Células Eucarióticas/metabolismo , Genômica/métodos , Histonas/genética , Histonas/história , Histonas/metabolismo , História do Século XXI , História Antiga , Humanos , Nucleossomos/química , Nucleossomos/metabolismo , Células Procarióticas/citologia , Células Procarióticas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/história , Fatores de Transcrição/metabolismo
7.
Protoplasma ; 254(3): 1151-1162, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27943022

RESUMO

Scientific discoveries and technological advancements are inseparable but not always take place in a coherent chronological manner. In the next, we will provide a seemingly unconnected and serendipitous series of scientific facts that, in the whole, converged to unveil DNA and its duplication. We will not cover here the many and fundamental contributions from microbial genetics and in vitro biochemistry. Rather, in this journey, we will emphasize the interplay between microscopy development culminating on super resolution fluorescence microscopy (i.e., nanoscopy) and digital image analysis and its impact on our understanding of DNA duplication. We will interlace the journey with landmark concepts and experiments that have brought the cellular DNA replication field to its present state.


Assuntos
Replicação do DNA/fisiologia , DNA/história , Processamento de Imagem Assistida por Computador/métodos , Microscopia de Fluorescência/métodos , DNA/biossíntese , DNA/genética , Proteínas de Fluorescência Verde , História do Século XIX , História do Século XX , História do Século XXI , Humanos
8.
PLoS Biol ; 14(12): e2001197, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28006030

RESUMO

This speculative Essay explores the consequences of the imagined premature death of Oswald Avery, who in 1944 provided evidence that genes are made of DNA. Four imaginary alternate routes to the genetic function of DNA are outlined, each of which highlights different aspects of the actual process of discovery.


Assuntos
DNA/história , Genes , História do Século XX , Humanos
9.
PLoS One ; 11(10): e0164659, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27741281

RESUMO

The human head louse, Pediculus humanus capitis, is subdivided into several significantly divergent mitochondrial haplogroups, each with particular geographical distributions. Historically, they are among the oldest human parasites, representing an excellent marker for tracking older events in human evolutionary history. In this study, ancient DNA analysis using real-time polymerase chain reaction (qPCR), combined with conventional PCR, was applied to the remains of twenty-four ancient head lice and their eggs from the Roman period which were recovered from Israel. The lice and eggs were found in three combs, one of which was recovered from archaeological excavations in the Hatzeva area of the Judean desert, and two of which found in Moa, in the Arava region, close to the Dead Sea. Results show that the head lice remains dating approximately to 2,000 years old have a cytb haplogroup A, which is worldwide in distribution, and haplogroup B, which has thus far only been found in contemporary lice from America, Europe, Australia and, most recently, Africa. More specifically, this haplogroup B has a B36 haplotype, the most common among B haplogroups, and has been present in America for at least 4,000 years. The present findings confirm that clade B lice existed, at least in the Middle East, prior to contacts between Native Americans and Europeans. These results support a Middle Eastern origin for clade B followed by its introduction into the New World with the early peoples. Lastly, the presence of Acinetobacter baumannii DNA was demonstrated by qPCR and sequencing in four head lice remains belonging to clade A.


Assuntos
Variação Genética , Pediculus/genética , Animais , Sequência de Bases , Citocromos b/genética , DNA/história , DNA/isolamento & purificação , DNA/metabolismo , Haplótipos , História Antiga , Humanos , Israel , Funções Verossimilhança , Dados de Sequência Molecular , Óvulo/metabolismo , Pediculus/classificação , Pediculus/crescimento & desenvolvimento , Filogenia , RNA Ribossômico/química , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Alinhamento de Sequência
10.
Clin Microbiol Infect ; 22(11): 911-915, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27615720

RESUMO

Plague, a deadly zoonose caused by the bacterium Yersinia pestis, has been firmly documented in 39 historical burial sites in Eurasia that date from the Bronze Age to two historical pandemics spanning the 6th to 18th centuries. Palaeomicrobiologic data, including gene and spacer sequences, whole genome sequences and protein data, confirmed that two historical pandemics swept over Europe from probable Asian sources and possible two-way-ticket journeys back from Europe to Asia. These investigations made it possible to address questions regarding the potential sources and routes of transmission by completing the standard rodent and rodent-flea transmission scheme. This suggested that plague was transmissible by human ectoparasites such as lice, and that Y. pestis was able to persist for months in the soil, which is a source of reinfection for burrowing mammals. The analyses of seven complete genome sequences from the Bronze Age indicated that Y. pestis was probably not an ectoparasite-borne pathogen in these populations. Further analyses of 14 genomes indicated that the Justinian pandemic strains may have formed a clade distinct from the one responsible for the second pandemic, spanning in Y. pestis branch 1, which also comprises the third pandemic strains. Further palaeomicrobiologic studies must tightly connect with historical and anthropologic studies to resolve questions regarding the actual sources of plague in ancient populations, alternative routes of transmission and resistance traits. Answering these questions will broaden our understanding of plague epidemiology so we may better face the actuality of this deadly infection in countries where it remains epidemic.


Assuntos
DNA/análise , Peste/epidemiologia , Peste/história , Yersinia pestis/genética , Ásia/epidemiologia , DNA/história , Europa (Continente)/epidemiologia , Evolução Molecular , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História Medieval , Humanos , Paleografia , Pandemias , Peste/microbiologia
11.
Hastings Cent Rep ; 46(5): 11-3, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27649823

RESUMO

On Saturday morning, February 28, 1953, the mystery of heredity appeared secure. Humans hadn't the faintest idea of how genetic information was transmitted-how the uncanny resemblance between mother and daughter, grandfather and grandson was conveyed across generations. Yet, by that Saturday afternoon, two individuals, James Watson and Francis Crick, had glimpsed the solution to these mysteries. The story of Watson and Crick's great triumph has been told and retold and has rightly entered the pantheon of scientific legend. But Watson and Crick's breakthrough was just that: a rupture and dramatic discontinuity in human knowledge that solved a deep mystery, the likes of which occurs, perhaps, a couple of times each century. And that's the problem. The story is just so good and so irresistible that it has misled generations of scientists about what to expect regarding a life in science. And more damaging, the resulting breakthrough mentality misleads the public, the media, and society's decision-makers about how science really works, all to the detriment of scientific progress and our society's well-being.


Assuntos
Pesquisa Biomédica/história , DNA/história , Simulação de Dinâmica Molecular/história , História do Século XX , Humanos , Filosofia Médica
14.
Arq Neuropsiquiatr ; 74(4): 351-3, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27097009

RESUMO

The year 2016 marks the centenary of the birth of Francis Crick (1916-2004), who made outstanding contributions to genetics and neuroscience. In 1953, in a collaborative study, Francis Crick and James Watson discovered the DNA double helix, and in 1962 they and Maurice Wilkins were awarded the Noble Prize in Physiology or Medicine. Crick subsequently became very interested in neuroscience, particularly consciousness and its relationship to the claustrum, a small gray matter structure between the insula and putamen.


Assuntos
Genética/história , Neurociências/história , Gânglios da Base/fisiologia , DNA/história , História do Século XX , História do Século XXI , Prêmio Nobel
16.
Gene ; 582(1): 94-5, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-26855436

RESUMO

How and when the first DNA sequence of a gene was determined? In 1977, F. Sanger came up with an innovative technology to sequence DNA by using chain terminators, and determined the entire DNA sequence of the 5375-base genome of bacteriophage φX 174 (Sanger et al., 1977). While this Sanger's achievement has been recognized as the first DNA sequencing of genes, we had determined DNA sequence of a gene, albeit a partial sequence, 11 years before the Sanger's DNA sequence (Okada et al., 1966).


Assuntos
DNA/história , Análise de Sequência de DNA/história , História do Século XX , Humanos , Análise de Sequência de DNA/métodos
17.
DNA Repair (Amst) ; 37: A35-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26861186

RESUMO

This article reviews the early history of the discovery of an DNA repair pathway designated as base excision repair (BER), since in contrast to the enzyme-catalyzed removal of damaged bases from DNA as nucleotides [called nucleotide excision repair (NER)], BER involves the removal of damaged or inappropriate bases, such as the presence of uracil instead of thymine, from DNA as free bases.


Assuntos
Bioquímica/história , Reparo do DNA , Mutagênese , Bactérias/metabolismo , DNA/história , DNA/metabolismo , Enzimas Reparadoras do DNA , Eucariotos/metabolismo , História do Século XX , História do Século XXI , Prêmio Nobel
18.
Genome Biol ; 17: 1, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26753840

RESUMO

Ancient DNA research is revealing a human history far more complex than that inferred from parsimonious models based on modern DNA. Here, we review some of the key events in the peopling of the world in the light of the findings of work on ancient DNA.


Assuntos
DNA/genética , História Antiga , Seleção Genética/genética , DNA/história , Migração Humana/história , Humanos
19.
J Steroid Biochem Mol Biol ; 157: 3-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25797032

RESUMO

This review summarizes the birth of the field of nuclear receptors, from Jensen's discovery of estrogen receptor alpha, Gustafsson's discovery of the three-domain structure of the glucocorticoid receptor, the discovery of the glucocorticoid response element and the first partial cloning of the glucocorticoid receptor. Furthermore the discovery of the novel receptors called orphan receptors is described.


Assuntos
Bioquímica/história , Receptores Nucleares Órfãos/história , Animais , Clonagem Molecular , DNA/história , DNA/metabolismo , História do Século XX , História do Século XXI , Humanos , Receptores Nucleares Órfãos/química , Receptores Nucleares Órfãos/fisiologia , Receptores Estrogênicos/química , Receptores Estrogênicos/metabolismo , Receptores de Glucocorticoides/química , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Elementos de Resposta
20.
Postepy Biochem ; 61(3): 298-304, 2015.
Artigo em Polonês | MEDLINE | ID: mdl-26677577

RESUMO

Environment of human being usually contains a high number of environmental mutagens, which may modify chemically nucleic acid bases into promutagenic analogues. Hydroxylamine (NH2OH) is a strong mutagen which modifies cytosine and adenine to N4-hydroxycytosine and N6-hydroxyadenine, respectively. Once these analogues are present in DNA or RNA, they may cause transition point mutations by the exchange between two pairs C:G and A:T into T:A and G:C, respectively. The reason for these mutations is the change of preferences between intermolecular hydrogen bonds resulting from the shift of the tautomeric equilibrium from the preferred amino form into the imino one. In the case of the amino<-->imino tautomeric equilibrium of N6-hydroxyadenosine, it was also shown that preferential hydrogen bonding between its imino form and cytidine, or uridine and the amino form of this base leads to the shift of the tautomeric equilibrium in favour of these tautomers in solution. N4-hydroxy-dCMP analogues exhibited very interesting inhibitory properties versus the biosynthesis of dTMP catalyzed by thymidylate synthase. These properties help to further the knowledge on the molecular mechanism of the catalytic reaction of this enzyme as well as on the role of syn-anti photoisomerization of the N4-hydroxy group in this reaction. Examinations gathered in the article were conducted from 1979 to 1985 under supervision, and afterwards from 1986 to 2004 in collaboration with professor David Shugar.


Assuntos
Adenina/análogos & derivados , Pareamento de Bases , Bioquímica/história , Citosina/análogos & derivados , Genética/história , Mutagênese , Adenina/química , Adenina/história , Adenina/metabolismo , Citosina/química , Citosina/história , Citosina/metabolismo , DNA/química , DNA/história , Dano ao DNA , História do Século XX , História do Século XXI , Ligações de Hidrogênio , Isomerismo , Mutação Puntual , Polônia
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