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1.
J Morphol ; 284(7): e21604, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37313770

RESUMO

Stenodus leucichthys nelma is an economically important species for cold-water aquaculture. Unlike other Coregoninae, S. leucichthys nelma is a piscivore. Here, we describe in detail the development of the digestive system and the yolk syncytial layer from hatching to early juvenile stage using histological and histochemical methods to determine their common and specific characteristics and to test the hypothesis that the digestive system of S. leucichthys nelma rapidly acquires adult features. The digestive tract differentiates at hatching and starts to function before the transition to mixed feeding. The mouth and anus are open, mucous cells and taste buds are present in the buccopharyngeal cavity and esophagus, pharyngeal teeth have erupted, the stomach primordium is seen, the intestinal epithelium with mucous cells is folded and the intestinal valve is observed; the epithelial cells of the postvalvular intestine contain supranuclear vacuoles. The liver blood vessels are filled with blood. The cells of exocrine pancreas are loaded with zymogen granules, and at least two islets of Langerhans are present. However, the larvae remain dependent on maternal yolk and lipids for a long time. The adult features of the digestive system develop gradually, the most significant changes take place approximately from 31 to 42 days posthatching. Then, the gastric glands and pyloric caeca buds appear, the U-shaped stomach with glandular and aglandular regions develops, the swim bladder inflates, the number of islets of Langerhans increases, the pancreas becomes scattered, and the yolk syncytial layer undergoes programmed death during the larval-to-juvenile transition. During postembryonic development, the mucous cells of the digestive system contain neutral mucosubstances.


Assuntos
Salmonidae , Animais , Citoplasma , Larva , Trato Gastrointestinal , Vesículas Secretórias
2.
Mol Phylogenet Evol ; 160: 107136, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33684529

RESUMO

Plastids and mitochondria have their own small genomes, which do not undergo meiotic recombination and may have evolutionary fates different from each other and that of the nuclear genome. For the first time, we sequenced mitochondrial genomes of pea (Pisum L.) from 42 accessions mostly representing diverse wild germplasm from throughout the wild pea geographical range. Six structural types of the pea mitochondrial genome were revealed. From the same accessions, plastid genomes were sequenced. Phylogenetic trees based on the plastid and mitochondrial genomes were compared. The topologies of these trees were highly discordant, implying not less than six events of hybridisation between diverged wild peas in the past, with plastids and mitochondria differently inherited by the descendants. Such discordant inheritance of organelles could have been driven by plastid-nuclear incompatibility, which is known to be widespread in crosses involving wild peas and affects organellar inheritance. The topology of the phylogenetic tree based on nucleotide sequences of a nuclear gene, His5, encoding a histone H1 subtype, corresponded to the current taxonomy and resembled that based on the plastid genome. Wild peas (Pisum sativum subsp. elatius s.l.) inhabiting Southern Europe were shown to be of hybrid origin, resulting from crosses of peas related to those presently inhabiting the eastern Mediterranean in a broad sense. These results highlight the roles of hybridisation and cytonuclear conflict in shaping plant microevolution.


Assuntos
Evolução Molecular , Genoma Mitocondrial/genética , Filogenia , Pisum sativum/citologia , Pisum sativum/genética , Plastídeos/genética , Núcleo Celular/genética , Citoplasma/genética , Europa (Continente) , Hibridização Genética
3.
Plants (Basel) ; 9(1)2019 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-31878042

RESUMO

Genetic analysis of nuclear-cytoplasm incompatibilities is not straightforward and requires an elaborated experimental design. A number of species have been genetically studied, but notable advances in genetic mapping of nuclear loci involved in nuclear-plastid incompatibility have been achieved only in wheat and pea. This review focuses on the study of the genetic background underlying nuclear-plastid incompatibilities, including cases where the molecular genetic basis of such incompatibility has been unveiled, such as in tobacco, Oenothera, pea, and wheat.

4.
Mol Phylogenet Evol ; 129: 280-290, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30195476

RESUMO

Organellar genomes may shed light on complicated patterns of plant evolution at inter- and intraspecies level. Primary structure of plastid genomes sequenced in this study and taken from public databases was characterised and compared in 22 diverse, mostly wild representatives of the genus Pisum (peas). Phylogenetic trees reconstructed via Bayesian approach on the basis of entire plastid genomes resembled those reconstructed on the basis of a nuclear gene His5 coding for a minor histone H1 subtype. They reveal Pisum fulvum as an early divergence of the genus but do not support other taxonomical subdivisions. The positions of three accessions, classified as P. sativum subsp. elatius (the wild subspecies of the common pea), appeared quite unexpected. On the entire plastid genome tree, two accessions, from the Black Sea area of Turkey and Georgia, clustered with representatives of another species, P. fulvum, while the other, from Greece, was the first divergence of the P. sativum branch. We suppose these unusual plastid genomes to be ancient lineages ascending to a 'missing link' between P. fulvum and P. sativum, represented by accession Pe 013 from Turkey. Accessions with common pea appearance but deeply diverged plastids could occur through occasional crossing of diverged pea lines in the past and biparental plastid inheritance, both events being possible in peas.


Assuntos
Genomas de Plastídeos , Filogenia , Pisum sativum/classificação , Pisum sativum/genética , Sequência de Bases , Teorema de Bayes , Mar Negro , Núcleo Celular/genética , Genes de Plantas , Grécia , Mutação/genética , Plastídeos/genética , Turquia
5.
Aging Dis ; 7(1): 81-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26815098

RESUMO

Chronic inflammatory diseases are associated with increases in cardiovascular diseases (CVD) and subclinical atherosclerosis as well as early-stage endothelial dysfunction screening using the FMD method (Flow Mediated Dilation). This phenomenon, referred to as accelerated pathological remodeling of arterial wall, could be attributed to traditional risk factors associated with atherosclerosis. Several new non-invasive techniques have been used to study arterial wall's structural and functional alterations. These techniques (based of Radio Frequency, RF) allow for an assessment of artery age through calculations of intima-media thickness (RF- QIMT), pulse wave rate (RF- QAS) and endothelial dysfunction degree (FMD). The inflammatory and autoimmune diseases should now be considered as new cardiovascular risk factors, result of the major consequences of oxidative stress and RAS (Renin Angiotensin System) imbalance associated with the deleterious effect of known risk factors that lead to the alteration of the arterial wall. Inflammation plays a key role in all stages of the formation of vascular lesions maintained and exacerbated by the risk factors. The consequence of chronic inflammation is endothelial dysfunction that sets in and we can define it as an integrated marker of the damage to arterial walls by classic risk factors. The atherosclerosis, which develops among these patients, is the main cause for cardiovascular morbi-mortality and uncontrolled chronic biological inflammation, which quickly favors endothelial dysfunction. These inflammatory and autoimmune diseases should now be considered as new cardiovascular risk factors.

6.
PLoS One ; 10(3): e0119835, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25789472

RESUMO

In crosses of wild and cultivated peas (Pisum sativum L.), nuclear-cytoplasmic incompatibility frequently occurs manifested as decreased pollen fertility, male gametophyte lethality, sporophyte lethality. High-throughput sequencing of plastid genomes of one cultivated and four wild pea accessions differing in cross-compatibility was performed. Candidate genes for involvement in the nuclear-plastid conflict were searched in the reconstructed plastid genomes. In the annotated Medicago truncatula genome, nuclear candidate genes were searched in the portion syntenic to the pea chromosome region known to harbor a locus involved in the conflict. In the plastid genomes, a substantial variability of the accD locus represented by nucleotide substitutions and indels was found to correspond to the pattern of cross-compatibility among the accessions analyzed. Amino acid substitutions in the polypeptides encoded by the alleles of a nuclear locus, designated as Bccp3, with a complementary function to accD, fitted the compatibility pattern. The accD locus in the plastid genome encoding beta subunit of the carboxyltransferase of acetyl-coA carboxylase and the nuclear locus Bccp3 encoding biotin carboxyl carrier protein of the same multi-subunit enzyme were nominated as candidate genes for main contribution to nuclear-cytoplasmic incompatibility in peas. Existence of another nuclear locus involved in the accD-mediated conflict is hypothesized.


Assuntos
Acetil-CoA Carboxilase/genética , Nucléolo Celular/genética , Citoplasma/genética , Pisum sativum/genética , Genoma de Planta , Sequenciamento de Nucleotídeos em Larga Escala , Dados de Sequência Molecular , Plastídeos/genética
7.
Clin Interv Aging ; 8: 573-80, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23761967

RESUMO

Atherosclerosis is a leading cause of cardiovascular death due to the increasing prevalence of the disease and the impact of risk factors such as diabetes, obesity or smoking. Sudden cardiac death is the primary consequence of coronary artery disease in 50% of men and 64% of women. Currently the only available strategy to reduce mortality in the at-risk population is primary prevention; the target population must receive screening for atherosclerosis. The value of screening for subclinical atherosclerosis is still relevant, it has become standard clinical practice with the emergence of new noninvasive techniques (radio frequency [RF] measurement of intima-media thickness [RFQIMT] and arterial stiffness [RFQAS], and flow-mediated vasodilatation [FMV]), which have been used by our team since 2007 and are based on detection marker integrators which reflect the deleterious effect of risk factors on arterial remodeling before the onset of clinical events. These techniques allow the study of values according to age and diagnosis of the pathological value, the thickness of the intima media (RFQIMT), the speed of the pulse wave (RFQAS), and the degree of endothelial dysfunction (FMV). This screening is justified in asymptomatic patients with cardiovascular risk factors (hypertension, diabetes, obesity, dyslipidemia, and tobacco smoking). Studies conducted by RF coupled with two-dimensional echo since 2007 have led to a more detailed analysis of the state of the arterial wall. The various examinations allow an assessment of the degree of subclinical atherosclerosis and its impact on arterial remodeling and endothelial function. The use of noninvasive imaging in screening and early detection of subclinical atherosclerosis is reliable and reproducible and allows us to assess the susceptibility of our patients with risk factors and ensures better monitoring of atherosclerosis, thus reducing the occurrence of cardiovascular events in the long term.


Assuntos
Aterosclerose/diagnóstico , Biomarcadores/análise , Velocidade do Fluxo Sanguíneo , Espessura Intima-Media Carotídea , Ecocardiografia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Valor Preditivo dos Testes , Ondas de Rádio , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Rigidez Vascular , Vasodilatação
8.
Mol Biol Rep ; 39(12): 10681-95, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23053965

RESUMO

A number of alleles of an orthologous gene His6 encoding histone H1 subtype f (H1-6 in pea) accumulated in chromatin of old tissues were sequenced in three legume species: seven alleles in Pisum sativum, four in Vicia unijuga and eight in Lathyrus gmelinii. In the total of 19 alleles sequenced in the three species, 29 non-synonymous substitutions and six indels were found in the coding region; most of amino acid substitutions (26 of 29) and all indels occurred in the C-terminal hydrophilic domain of the encoded protein. All species were polymorphic for some non-synonymous substitutions, V. unijuga was also polymorphic for one and P. sativum for two indels. Three near-isogenic lines of P. sativum bearing different alleles showed differences in many quantitative traits; that in the growth dynamic could be tentatively attributed to the allelic substitution of subtype H1-6. The frequencies of four electromorphs in a sampled locality of V. unijuga were found to be close to those observed 25 years ago, although their rapid change in the past was supposed in the previous study.


Assuntos
Fabaceae/genética , Histonas/química , Histonas/genética , Polimorfismo Genético , Alelos , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Eletroforese em Gel de Ágar , Fabaceae/anatomia & histologia , Histonas/isolamento & purificação , Mutação INDEL/genética , Íntrons/genética , Lathyrus/anatomia & histologia , Lathyrus/genética , Dados de Sequência Molecular , Nucleotídeos/genética , Pisum sativum/anatomia & histologia , Pisum sativum/genética , Estrutura Terciária de Proteína , Característica Quantitativa Herdável , Alinhamento de Sequência , Especificidade da Espécie , Vicia/anatomia & histologia , Vicia/genética
9.
Gene ; 504(2): 192-202, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-22613846

RESUMO

A phylogenetic analysis of the genus Pisum (peas), embracing diverse wild and cultivated forms, which evoke problems with species delimitation, was carried out based on a gene coding for histone H1, a protein that has a long and variable functional C-terminal domain. Phylogenetic trees were reconstructed on the basis of the coding sequence of the gene His5 of H1 subtype 5 in 65 pea accessions. Early separation of a clear-cut wild species Pisum fulvum is well supported, while cultivated species Pisum abyssinicum appears as a small branch within Pisum sativum. Another robust branch within P. sativum includes some wild and almost all cultivated representatives of P. sativum. Other wild representatives form diverse but rather subtle branches. In a subset of accessions, PsbA-trnH chloroplast intergenic spacer was also analysed and found less informative than His5. A number of accessions of cultivated peas from remote regions have a His5 allele of identical sequence, encoding an electrophoretically slow protein product, which earlier attracted attention as likely positively selected in harsh climate conditions. In PsbA-trnH, a 8bp deletion was found, which marks cultivated representatives of P. sativum.


Assuntos
Histonas/genética , Pisum sativum/genética , Sequência de Bases , Primers do DNA , Filogenia , Reação em Cadeia da Polimerase , Especificidade da Espécie
10.
Theor Appl Genet ; 124(8): 1503-12, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22318398

RESUMO

Genetic analysis was performed to finely map and assess the mode of inheritance of two unlinked nuclear genes Scs1 and Scs2 involved in incompatibility of the nuclear genome of the cultivated pea Pisum sativum subsp. sativum with the cytoplasm of the wild pea of the subspecies P. sativum subsp. elatius, accession VIR320. Based on the segregation of genotypes in the progeny of the test-crosses, we concluded that if the cytoplasm was inherited from the wild pea VIR320, the Scs1 allele from the cultivated pea was gametophyte lethal and sporophyte recessive lethal. The Scs2 allele from the cultivated pea reduced male gametophyte viability. In homozygote, Scs2 from cultivated parent brought about nuclear-cytoplasmic conflict manifested as chlorophyll deficiency, reduction of blade organs, and low pollen fertility of about 20%. In heterozygote, Scs1 and Scs2 genes reduced pollen fertility by ca 50 and 30%, respectively. The Scs1 and Scs2 genes involved in nuclear-cytoplasmic incompatibility were genetically mapped. The distance between the markers bordering Scs1 comprised about 2.5 cM on linkage group III. The map distance between the bordering markers in the neighborhood of Scs2 varied substantially from cross to cross in the range of 2.0-15.1 cM on linkage group V.


Assuntos
Núcleo Celular/metabolismo , Mapeamento Cromossômico/métodos , Citoplasma/metabolismo , Pisum sativum/genética , Alelos , Clorofila/genética , Cruzamentos Genéticos , Citoplasma/genética , Endonucleases/metabolismo , Genes de Plantas , Ligação Genética , Marcadores Genéticos/genética , Heterozigoto , Modelos Genéticos , Fenótipo , Plastídeos/metabolismo , Pólen/química , Pólen/metabolismo
11.
Theor Appl Genet ; 118(4): 801-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19099285

RESUMO

The genetic basis of nuclear-cytoplasmic incompatibility was examined using the wild pea (Pisum sativum subsp. elatius) accession VIR320. When this accession is used as the female parent in crosses with domesticated peas (Pisum sativum subsp. sativum) the F(1) is highly sterile and displays chlorophyll deficiency, chlorophyll variegation, reduction of leaflets and stipulae while the reciprocal cross produces hybrids that appear normal. A mapping recombinant inbred line (RIL) population was established based on a cross in a compatible direction of a tester line WL1238 with VIR320. The ability to cause nuclear-cytoplasmic conflict was analysed by crossing individual RIL plants as pollen parents with VIR320 as donor of cytoplasm and scoring each F(1) for major signs of the conflict. It is concluded that two unlinked nuclear genes are involved in the genetic control of the observed incompatibility. One of the genes, denoted as Scs1, is closely linked to the PhlC gene on linkage group III and the other, denoted as Scs2, is closely linked to the gp gene on linkage group V. Alleles of both genes in WL1238 are dominant and appear to be lethal in the homozygous condition in the VIR320 cytoplasm background.


Assuntos
Núcleo Celular/genética , Cloroplastos/genética , Citoplasma/genética , DNA de Plantas/genética , Pisum sativum/genética , Mapeamento Cromossômico , Cruzamentos Genéticos , Primers do DNA/genética , Marcadores Genéticos/genética , Reação em Cadeia da Polimerase
12.
Rejuvenation Res ; 11(2): 393-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18393653

RESUMO

Oxidative stress (OS) is a keystone in the pathology of the ischemia reperfusion sequence (acute coronary syndromes, cardiac surgery, transplantation). In heart failure, the implication of OS is less understood. This study was intended to evaluate OS in acute heart failure. Criteria for inclusion were consecutive patients hospitalized in our cardiology department for a first pulmonary edema that revealed a dilated cardiomyopathy (DCM). Exclusion criteria included known cardiomyopathy, smoker, acute coronary syndrome, and treatment with angiotensin converting enzyme inhibitors (ACEI) or angiotensin II receptor blockers (ARAII). OS was evaluated in blood samples: thiobarbituric acid-reactive substances (TBARS), total antioxidant status (TAS), plasma alpha-tocopherol, vitamin A, and beta-carotene. Standard biochemical parameters including CRP, fibrinogen, lipid, and creatinine were assayed. Ten patients (80% men, mean age 55.3 +/- 7.9 years) were included and followed during a 6 month period. The etiologies of DCM were alcohol (n = 3), anti-cancer drugs (n = 2), valvulopathies (n = 2), or idiopathic (n = 3). In acute heart failure, TBARS were elevated (1.69 micromol/L; normal value 0.6-4.2 micromol/L) and TAS status was decreased (0.96 mmol/L; normal value 1.3-1.9 pmol/L). OS was more important when patients had atrial or ventricular arrhythmia. Nevertheless, liposoluble antioxidant parameters (beta-carotene, vitamin A, alpha-tocopherol) had a usual value. At the term of the follow-up, patients returned to a stable condition, OS markers revealed normal values, and every Holter ECG showed no supraventricular or ventricular arrhythmias. In acute heart failure, oxygen-free radicals are increased. We thus hypothetized that a modification in OS could be responsible for arrhythmias and complications of acute heart failure.


Assuntos
Insuficiência Cardíaca/metabolismo , Estresse Oxidativo , Doença Aguda , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Genetica ; 130(1): 61-72, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-16900316

RESUMO

In pea, subtype H1-7 of histone H1 is specific for young actively growing tissues and disappears from chromatin of mature tissues. We sequenced the alleles coding for three main variants, numbered according to the increase of the electrophoretic mobility. Allele 1 differs from the most common allele 2 by eight nucleotide substitutions, two of them associated with amino acid replacements, His->Tyr in the globular domain and Ala->Val in the C-terminal domain. Allele 3 differs from alleles 1 and 2 by a 24-bp deletion in the part coding for the C-terminal domain. In three greenhouse experiments, we compared quantitative traits in nearly isogenic lines differing by these H1-7 variants. In experiment 1, three lines bearing either of the three allelic variants were compared, the other experiments involved pairs of lines bearing variants 1 and 3. In all experiments, statistically significant differences between the lines were registered, mostly related to the plant size. The most prominent effect was associated with plant growth dynamics. Plants of line 3, carrying the 8-amino acid deletion in histone H1-7, on average grew slower. In two experiments, the differences of the mean stem length persisted throughout plant growth while in experiment 2 differences disappeared upon maturity. The H1-7 subtype is supposed to be related to maintenance of chromatin state characteristic for cell growth and division.


Assuntos
Alelos , Histonas/genética , Fenótipo , Pisum sativum/crescimento & desenvolvimento , Pisum sativum/genética , Sequência de Aminoácidos , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Isoformas de Proteínas/genética , Homologia de Sequência de Aminoácidos
14.
Theor Appl Genet ; 114(2): 333-9, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17080258

RESUMO

An unusual biparental mode of plastid inheritance was found in pea, in a cross associated with nuclear-cytoplasmic incompatibility manifested as deficiency of chlorophyll pigmentation. Plastid DNA marker trnK and mitochondrial DNA marker cox1 were analyzed in F1 progeny that received cytoplasm from an accession of a wild subspecies Pisum sativum ssp. elatius. Plants with sectors of green tissue on leaves and seed cotyledons with green patches on an otherwise chlorotic background were found to carry paternally inherited plastid DNA, suggesting that photosynthetic function was affected by nuclear-cytoplasmic conflict and required proliferation of paternally inherited plastids for normal performance. The paternally inherited plastid DNA marker was also observed in the roots. The presence of the paternal marker in cotyledons, roots and leaves was independent of each other. Inheritance of the mitochondrial DNA marker cox1 appeared to be of the maternal type.


Assuntos
Núcleo Celular/genética , Cloroplastos/genética , Cruzamentos Genéticos , Citoplasma/genética , DNA Mitocondrial/genética , DNA de Plantas/genética , Organelas/genética , Pisum sativum/genética , Marcadores Genéticos
15.
Genomics ; 88(6): 752-761, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16725306

RESUMO

The mouse PancChip, a microarray developed for studying endocrine pancreatic development and diabetes, represents over 13,000 cDNAs. After computationally assigning the cDNAs on the array to known genes, manual curation of the remaining sequences identified 211 novel transcripts. In microarray experiments, we found that 196 of these transcripts were expressed in total pancreas and/or pancreatic islets. Of 50 randomly selected clones from these 196 transcripts, 92% were confirmed as expressed by qRT-PCR. We evaluated the coding potential of the novel transcripts and found that 74% of the clones had low coding potential. Since the transcripts may be partial mRNAs, we examined their translated proteins for transmembrane or signal peptide domains and found that about 40 proteins had one of these predicted domains. Interestingly, when we investigated the novel transcripts for their overlap with noncoding microRNAs, we found that 1 of the novel transcripts overlapped a known microRNA gene.


Assuntos
Ilhotas Pancreáticas/metabolismo , Análise em Microsséries/métodos , Pâncreas/metabolismo , Proteínas/genética , Animais , Clonagem Molecular , Biologia Computacional/métodos , DNA Complementar , Diabetes Mellitus Tipo 1/genética , Perfilação da Expressão Gênica , Genoma , Camundongos , Camundongos Endogâmicos NOD , Transcrição Gênica
16.
J Mol Evol ; 59(4): 546-55, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15638466

RESUMO

An analysis of the histone H1 subtype, H1-1, in eight legumes belonging to four genera of the tribe Vicieae (Pisum, Lathyrus, Lens, and Vicia), revealed an extended region consisting of the tandemly repeated AKPAAK motifs. We named this region the Regular zone (RZ). The AKPAAK motifs are organized into two blocks separated by a short (two or six amino acids) intervening sequence (IS). The distal block contains six AKPAAK motifs, while the number of repeats in the proximal block varies from six in V. faba to seven in the other species. In V. hirsuta, the first two repeated units of the proximal block are octapeptides AKAKPAAK. The apparent rate of synonymous substitutions in the blocks of RZ is much higher than in the rest of the gene. This can be explained by repeat shuffling within each block. In the C-domain of the orthologous H1 subtype from Medicago truncatula (tribe Trifolieae), a region corresponding to the RZ of Vicieae species was found. It also consists of two blocks of AKPAAK motifs (four and three repeats in the proximal and distal blocks, respectively). These blocks are separated by a 20-amino acid IS. The first 20 amino acids of the Medicago RZ are not part of AKPAAK repeats. We hypothesise that the RZ has most probably evolved as a result of an expansion of AKPAAK repeats from two separate sites in the C-domain. This process started tens of millions of years ago and was most likely directed by positive selection.


Assuntos
Evolução Molecular , Fabaceae/genética , Histonas/genética , Sequência de Aminoácidos , Variação Genética , Histonas/classificação , Lathyrus/genética , Dados de Sequência Molecular , Pisum sativum/genética , Filogenia , Sequências Repetitivas de Aminoácidos/genética , Sementes/química , Sementes/genética , Alinhamento de Sequência , Vicia/genética
17.
Genetica ; 119(2): 167-82, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14620956

RESUMO

Electrophoretic analysis of the most abundant subtype of histone H1 (H1-1) of 301 accessions of grasspea (Lathyrus sativus) and 575 accessions of lentil (Lens culinaris) revealed allelic variants which most probably arose due to recent mutations. In each species, a single heterozygote for a mutation was taken for construction of isogenic lines carrying different H1-1 variants. Sequencing of alleles encoding H1-1 in lentil, grasspea, pea and Lathyrus aphaca showed the presence of an extended region in C-terminal tail which we termed 'regular zone' (RZ). It consists of 14 6-amino-acid units of which 12 (pea and Lathyrus species) or 13 (lentil) are represented by an AKPAAK sequence. The structure of the hypervariable unit 8 is species-specific. At the DNA level most AKPAAK units differ in the third codon positions, implying the action of natural selection preserving the RZ organization. In lentil, the fast variant lost two units (including unit 8), while one AKPAAK repeat of the slow variant is transformed into an anomalous SMPAAK. The mutant variant of the grasspea H1-1 differs from the standard one by duplication of an 11-amino-acid segment in N-terminal tail. The isogenic lines of lentil and grasspea were compared for a number of quantitative traits, some of them showing small (1-8%) significant differences.


Assuntos
Histonas/genética , Lens (Planta)/genética , Pisum sativum/genética , Alelos , Sequência de Aminoácidos , Sequência de Bases , Sequência Consenso , Eletroforese , Evolução Molecular , Histonas/química , Dados de Sequência Molecular , Característica Quantitativa Herdável , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
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