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1.
Dermatol Surg ; 43(12): 1448-1457, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28595250

RESUMO

BACKGROUND: There are requirements for long-term, objective comparisons of hyaluronic acid (HA) dermal fillers. OBJECTIVE: To compare efficacy and tolerability of ART FILLER Universal (AFU) and ART FILLER Fine lines (AFFL) with the existing HA fillers for the treatment of nasolabial folds and crow's feet. MATERIALS AND METHODS: Prospective, randomized, rater- and patient-blind, split-face comparison of AFU with JUVEDERM Ultra 3 (JUV) and AFFL with FIRST LINES PureSense (FLPS). The severity of nasolabial folds and crow's feet was assessed by independent blinded evaluators using the Lemperle scale at baseline, day (D) 30/D45, D90, and D180. Tolerability, Global Aesthetic Improvement Scale (GAIS), wrinkle volumes, and skin thickness and density were also measured at D30/D45, D90, and D180. RESULTS: At D30 and D180 respectively, 61 and 57 patients were assessed. Scores for nasolabial folds and crow's feet showed statistically significant improvements at D30, D90, and D180. AFU and AFFL were noninferior to JUV and FLPS, respectively. Most patients showed GAIS improvements, maintained until at least D180 and significant increases of collagen synthesis in crow's feet and nasolabial folds. Treatments were well tolerated. CONCLUSION: AFU and AFFL are noninferior to comparators. The methodology used represents a novel approach to augment existing clinical assessment of HA fillers.


Assuntos
Preenchedores Dérmicos/administração & dosagem , Ácido Hialurônico/administração & dosagem , Envelhecimento da Pele , Adulto , Idoso , Técnicas Cosméticas , Preenchedores Dérmicos/uso terapêutico , Olho , Feminino , Humanos , Ácido Hialurônico/uso terapêutico , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Sulco Nasogeniano , Estudos Prospectivos , Método Simples-Cego , Pele
2.
PLoS Genet ; 7(10): e1002314, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21998598

RESUMO

Morphological consistency in metazoans is remarkable given the pervasive occurrence of genetic variation, environmental effects, and developmental noise. Developmental stability, the ability to reduce developmental noise, is a fundamental property of multicellular organisms, yet its genetic bases remains elusive. Imperfect bilateral symmetry, or fluctuating asymmetry, is commonly used to estimate developmental stability. We observed that Drosophila melanogaster overexpressing Cyclin G (CycG) exhibit wing asymmetry clearly detectable by sight. Quantification of wing size and shape using geometric morphometrics reveals that this asymmetry is a genuine-but extreme-fluctuating asymmetry. Overexpression of CycG indeed leads to a 40-fold increase of wing fluctuating asymmetry, which is an unprecedented effect, for any organ and in any animal model, either in wild populations or mutants. This asymmetry effect is not restricted to wings, since femur length is affected as well. Inactivating CycG by RNAi also induces fluctuating asymmetry but to a lesser extent. Investigating the cellular bases of the phenotypic effects of CycG deregulation, we found that misregulation of cell size is predominant in asymmetric flies. In particular, the tight negative correlation between cell size and cell number observed in wild-type flies is impaired when CycG is upregulated. Our results highlight the role of CycG in the control of developmental stability in D. melanogaster. Furthermore, they show that wing developmental stability is normally ensured via compensatory processes between cell growth and cell proliferation. We discuss the possible role of CycG as a hub in a genetic network that controls developmental stability.


Assuntos
Ciclina G/fisiologia , Proteínas de Drosophila/fisiologia , Drosophila melanogaster/crescimento & desenvolvimento , Asas de Animais/crescimento & desenvolvimento , Animais , Sequência de Bases , Padronização Corporal/genética , Ciclina G/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Redes Reguladoras de Genes , Variação Genética , Genótipo , Dados de Sequência Molecular , Fenótipo , Interferência de RNA , Asas de Animais/anatomia & histologia
3.
Clin Cosmet Investig Dermatol ; 16: 1795-1805, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37465030

RESUMO

Purpose: Injectable hyaluronic acid-based fillers are commonly used for the correction of skin contour irregularities and to smooth skin depressions formed by volume loss during the aging process. These fillers are particularly efficient to restore perioral skin depressions/wrinkles or to correct topographical anomalies. The European directives require a continuous evaluation of the performance of these medical devices, particularly for CE marked products. Methods: An 18-month prospective randomized single-blind study for the efficacy and safety of ART FILLER Universal (AFU) was performed on the lips, the nasolabial folds, and the marionettes lines. The evaluations were performed on 153 subjects enrolled in this study. The efficacy, the longevity, and the safety were evaluated for the injected areas via area specific clinical scoring after a single injection with the filler and with no re-touch. Results: We showed here that filler injection induced potent improvements of volume restoration after a single injection on all the treated areas. These beneficial properties of the filler were significant 3 weeks after injection and during the whole study period. Moreover, injections of the filler were well tolerated by the subjects. The recorded adverse events are routinely seen with HA fillers for face volume corrections, and most of these local reactions resolved within 14 days. Conclusion: AFU was well tolerated and showed a continuous efficacy for at least 18 months, in exploratory analyses.

4.
J Dermatolog Treat ; 34(1): 2216323, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37577796

RESUMO

BACKGROUND: NCTF®135HA is a bio-revitalizing solution containing hyaluronic acid designed to compensate for skin dehydration, fatigue, and fine wrinkles associated with endogenous and environmental aging. METHODS: We conducted a randomized, active-controlled study to evaluate the efficacy and tolerability of NCTF®135HA injections on the face (crow's feet), neck, and décolleté regions. Subjects were randomly assigned (3:1) to receive three NCTF®135HA treatment sessions plus twice-daily anti-aging moisturizer cream or cream alone (control). The primary outcome was the reduction in superficial wrinkles between baseline and Day (D)75 in the three areas, assessed by profilometric measures, clinical scoring, subjective changes, and tolerability. RESULTS: 146 subjects were randomized to NCTF®135HA (n = 107) or control (n = 38). At D75 and D120, NCTF®135HA significantly reduced wrinkles in all three areas and improved facial radiance scores compared with the control. Skin hydration significantly increased 7 d after the last NCTF®135HA injection. Self-esteem scales showed statistically significant improvements at D75 and D120 in subjects treated with NCTF®135HA versus baseline. Most adverse events were mild, resolved within 48 h, and were related to the injection procedure. CONCLUSION: NCTF®135HA is an effective and well-tolerated treatment to reduce the skin signs of aging. The results are significantly superior to a routine anti-aging cream alone.(Funded by Laboratories FILLMED; ID-RCB number: 2018-A03167-48; clinicaltrials.gov number: NCT05609617).


Assuntos
Ácido Hialurônico , Envelhecimento da Pele , Humanos , Estudos Prospectivos , Pele , Resultado do Tratamento , Rejuvenescimento
5.
J Cosmet Dermatol ; 22(2): 464-472, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35718985

RESUMO

BACKGROUND: Age-related changes of facial soft tissue cause clinical signs of facial aging such as lip atrophy, marionette lines, and an accentuated nasolabial fold. These changes can be modified using dermal fillers. AIMS: To evaluate efficacy, longevity, and safety of a cross-linked hyaluronic acid-based filler with Tri-Hyal technology in the treatment of lips, nasolabial folds, and marionette lines. MATERIALS AND METHODS: This prospective, multi-center trial evaluated injections of three different areas (lips, nasolabial fold alone, or with marionette wrinkles) with a soft tissue filler containing 25 mg/ml cross-linked hyaluronic acid and 0.3% lidocaine. Primary endpoint was the aesthetic correction 3 weeks after one injection session without touch-up. Follow-up was 18 months. Assessments were performed using the Global Aesthetic Score (GAS), clinical scoring based on photographic scales, high-frequency ultrasound imaging, and the Global Aesthetic Improvement Scale (GAIS). RESULTS: In total, 100 subjects were injected. GAS improved significantly for all treatment indications at 3 weeks (p < 0.0001). Success rates were highest for nasolabial folds (98.4%), followed by marionette lines (94.4%) and lips (73.5%). After 18 months post-injection, success was observed in 91%, 88%, and 33% of subjects injected into nasolabial folds, marionette lines, and lips, respectively. GAIS scored highest for nasolabial folds (SGAIS: 71%; IGAIS: 40%), followed by marionette lines (SGAIS: 56%; IGAIS: 33%) and lips (SGAIS: 30%; IGAIS: 22%) at 18 months follow-up. CONCLUSIONS: The filler demonstrated high efficacy and safety in all indications. Regional differences in longevity were evident. Thus, the necessity of regional retreatments should be discussed with patients before injection.


Assuntos
Técnicas Cosméticas , Preenchedores Dérmicos , Envelhecimento da Pele , Humanos , Lábio , Técnicas Cosméticas/efeitos adversos , Ácido Hialurônico/efeitos adversos , Estudos Prospectivos , Sulco Nasogeniano , Resultado do Tratamento , Preenchedores Dérmicos/efeitos adversos
6.
Nature ; 441(7092): 506-8, 2006 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-16724066

RESUMO

Arthropod head segments offer a paradigm for understanding the diversification of form during evolution, as a variety of morphologically diverse appendages have arisen from them. There has been long-running controversy, however, concerning which head appendages are homologous among arthropods, and from which ancestral arrangement they have been derived. This controversy has recently been rekindled by the proposition that the probable ancestral arrangement, with appendages on the first head segment, has not been lost in all extant arthropods as previously thought, but has been retained in the pycnogonids, or sea spiders. This proposal was based on the neuroanatomical analysis of larvae from the sea spider Anoplodactylus sp., and suggested that the most anterior pair of appendages, the chelifores, are innervated from the first part of the brain, the protocerebrum. Our examination of Hox gene expression in another sea spider, Endeis spinosa, refutes this hypothesis. The anterior boundaries of Hox gene expression domains place the chelifore appendages as clearly belonging to the second head segment, innervated from the second part of the brain, the deutocerebrum. The deutocerebrum must have been secondarily displaced towards the protocerebrum in pycnogonid ancestors. As anterior-most appendages are also deutocerebral in the other two arthropod groups, the Euchelicerata and the Mandibulata, we conclude that the protocerebral appendages have been lost in all extant arthropods.


Assuntos
Artrópodes/anatomia & histologia , Artrópodes/genética , Regulação da Expressão Gênica no Desenvolvimento , Genes Homeobox/genética , Cabeça/anatomia & histologia , Animais , Artrópodes/crescimento & desenvolvimento , Clonagem Molecular , Gânglios/crescimento & desenvolvimento , Larva/anatomia & histologia , Larva/genética , Larva/crescimento & desenvolvimento
7.
Adv Exp Med Biol ; 689: 155-65, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20795330

RESUMO

What is the function of the Hox genes? At first glance, it is a curious question. Indeed, the answer seems so obvious that several authors have spoken of 'the Hox function' about some of the Hox genes, namely Hox3/zen and Hox6/ftz that seem to have lost it during the evolution of Arthropods. What these authors meant is that these genes have lost their 'homeotic' function. Indeed, 'homeotic' refers to a functional property that is so often associated with the Hox genes. However, the word 'Hox' should not be used to refer to a function, but to a group of genes. The above examples of Hox3/zen (see Schmitt-Ott's chapter, this book) and Hox6/ftz show that the homeotic function may be not so tightly linked to the Hox genes. Reversely, many genes, not belonging to the Hox group, do present a homeotic function. In the present chapter, I will first give a definition of the Hox genes. I will then ask what is the 'function' of a gene, examining its various meanings at different levels of biological organization. I will review and revisit the relation between the Hox genes and homeosis. I will suggest that their morphological homeotic function has been secondarily derived during the evolution of the Bilateria.


Assuntos
Padronização Corporal/genética , Genes Homeobox , Animais , Evolução Biológica , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética
8.
Plast Reconstr Surg Glob Open ; 8(12): e3274, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33425589

RESUMO

The first phase of this study showed that ART FILLER Universal filler (AFU; FILORGA Laboratories) and ART FILLER Fine lines (AFFL) were non-inferior to JUVÉDERM Ultra 3 (Allergan) and FIRST LINES PureSense (Teoxane), respectively. The clinical benefits of AFU and AFFL on nasolabial folds and crow's feet persisted until at least Day 180. This article reports results from an open-label extension phase that assessed the tolerability and efficacy of AFU and AFFL for up to 18 months based on clinical evaluation and ultrasound high-frequency imaging. METHODS: Eligible subjects were enrolled at D180 and assessed on D270, D360, and D540. The primary outcome measured was local tolerability. Secondary outcomes measured included: proportion of subjects in whom the severity of nasolabial folds and crow's feet remained at least 1 point below the baseline measurement (Lemperle scale); general safety; Global Aesthetic Improvement Scale scores by subjects and investigators; wrinkle volumes; and skin thickness by high-frequency ultrasound. RESULTS: Adverse events were consistent with the product information and the initial study. No serious adverse events were recorded. In exploratory analyses, wrinkle correction with AFU and AFFL is sustained for at least 18 months: 48.4% and 98.3% of subjects respectively still showed at least a 1-point decrease in the mean Lemperle score compared with the baseline. The benefits were sustained irrespective of whether subjects received additional injections. Modifications in wrinkle volume and skin thickness at D540 were statistically significant compared with the baseline. CONCLUSION: AFU and AFFL were well tolerated and, in exploratory analyses, showed a sustained efficacy for at least 18 months.

9.
Nucleic Acids Res ; 31(11): 2873-82, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12771214

RESUMO

In Drosophila, PcG complexes provide heritable transcriptional silencing of target genes. Among them, the ESC/E(Z) complex is thought to play a role in the initiation of silencing whereas other complexes such as the PRC1 complex are thought to maintain it. PcG complexes are thought to be recruited to DNA through interaction with DNA binding proteins such as the GAGA factor, but no direct interactions between the constituents of PcG complexes and the GAGA factor have been reported so far. The Drosophila corto gene interacts with E(z) as well as with genes encoding members of maintenance complexes, suggesting that it could play a role in the transition between the initiation and maintenance of PcG silencing. Moreover, corto also interacts genetically with Trl, which encodes the GAGA factor, suggesting that it may serve as a mediator in recruiting PcG complexes. Here, we show that Corto bears a chromo domain and we provide evidence for in vivo association of Corto with ESC and with PC in embryos. Moreover, we show by GST pull-down and two-hybrid experiments that Corto binds to E(Z), ESC, PH, SCM and GAGA and co-localizes with these proteins on a few sites on polytene chromosomes. These results reinforce the idea that Corto plays a role in PcG silencing, perhaps by confering target specificity.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Proteínas de Homeodomínio/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Cromossomos/química , Proteínas de Ligação a DNA/análise , Proteínas de Ligação a DNA/química , Drosophila/embriologia , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/análise , Regulação da Expressão Gênica , Histona-Lisina N-Metiltransferase , Proteínas de Homeodomínio/análise , Substâncias Macromoleculares , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Complexo Repressor Polycomb 1 , Complexo Repressor Polycomb 2 , Testes de Precipitina , Estrutura Terciária de Proteína , Proteínas Repressoras/metabolismo , Alinhamento de Sequência , Análise de Sequência de Proteína , Fatores de Transcrição/análise , Técnicas do Sistema de Duplo-Híbrido
10.
Environ Sci Pollut Res Int ; 23(13): 13581-4, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27179812

RESUMO

The Cosmet'eau project (2015-2018) investigates the "changes in the personal care product (PCP) consumption practices: from whistle-blowers to impacts on aquatic environments." In this project, the example of PCPs will be used to understand how public health concerns related to micropollutants can be addressed by public authorities-including local authorities, industries, and consumers. The project aims to characterize the possible changes in PCP consumption practices and to evaluate the impact of their implementation on aquatic contamination. Our goals are to study the whistle-blowers, the risk perception of consumers linked with their practices, and the contamination in parabens and their substitutes, triclosan, and triclocarban from wastewater to surface water. The project investigates the following potential solutions: modifications of industrial formulation or changes in consumption practices. The final purpose is to provide policy instruments for local authorities aiming at building effective strategies to fight against micropollutants in receiving waters.


Assuntos
Monitoramento Ambiental , Produtos Domésticos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Carbanilidas , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Produtos Domésticos/análise , Produtos Domésticos/normas , Parabenos , Triclosan
11.
Mech Dev ; 110(1-2): 71-83, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11744370

RESUMO

The recent determination and annotation of the entire euchromatic sequence of the Drosophila melanogaster genome predicted the existence of about 13600 different genes (Science 287 (2000) 2185; http://www.fruitfly.org/annot/index.html). In parallel, the Berkeley Drosophila Genome Project (BDGP) has undertaken systematic P-insertion screens, to isolate new lethals and misexpressing lines. To date, however, the genes of the X chromosome have been under-represented in the screens performed. In order both to characterize several X-linked genes of prime interest to our laboratories and contribute to the collection of lethal P-insertions available to the community, we performed a P-insertion mutagenesis of the X chromosome. Using the PlacW and PGawB P-elements as mutagens, we generated two complementary sets of enhancer-trap lines, l(1)(T)PL and l(1)(T)PG, respectively, which both contain a reporter gene whose developmental expression can be monitored when driven by nearby enhancer sequences. We report here the characterization of 260 new insertions, mapping to 133 different genes or predicted CGs. Of these, 83 correspond to genes for which no lethal mutation had yet been reported. For 64 of those, we could confirm that lethality was solely due to the P-element insertion. The primary molecular data, reporter gene expression patterns (observed in embryos, third instar larvae and adult ovaries) and proposed CG assignment for each strain can be accessed and updated on our website at the following address: http://www-cbd.ups-tlse.fr:8080/screen.


Assuntos
Drosophila melanogaster/genética , Genes de Insetos , Animais , Animais Geneticamente Modificados , Cruzamentos Genéticos , Drosophila melanogaster/embriologia , Elementos Facilitadores Genéticos , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genes Letais , Genes Reporter , Ligação Genética , Óperon Lac , Masculino , Mutagênese Insercional , Cromossomo X/genética
14.
C R Biol ; 333(2): 99-106, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20338525

RESUMO

In this essay, I discuss the origin of Charles Darwin's interest in cirripedes (barnacles). Indeed, he worked intensively on cirripedes during the years in which he was developing the theory that eventually led to the publication of The Origin of Species. In the light of our present knowledge, I present Darwin's achievements in the morphology, systematics and biology of these small marine invertebrates, and also his mistakes. I suggest that the word that sheds the most light here is homology, and that his mistakes were due to following Richard Owen's method of determining homologies by reference to an ideal archetype. I discuss the ways in which his studies on cirripedes influenced the writing of The Origin.


Assuntos
História Natural/história , Thoracica/classificação , Estruturas Animais/anatomia & histologia , Animais , História do Século XIX , Larva/anatomia & histologia , Thoracica/anatomia & histologia , Thoracica/crescimento & desenvolvimento
15.
Integr Zool ; 4(3): 316-22, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21392304

RESUMO

Charles Darwin's favorite animals were cirripedes (barnacles). Indeed, he worked intensively on cirripedes during the years he was maturing his thoughts regarding his theory, which eventually led to the publication of The Origin of Species. Here I present some of Darwin's achievements in the morphology, systematics and biology of these small marine invertebrates, and also, in light of our present knowledge, some mistakes he made.


Assuntos
Evolução Biológica , Thoracica/anatomia & histologia , Thoracica/classificação , Thoracica/fisiologia , Animais
16.
Dev Genes Evol ; 216(7-8): 357-62, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16841233

RESUMO

In the present essay, I first recall the genealogical concept of classification settled by Charles Darwin in the "Origin of Species". Darwin tightly linked what we now call phylogeny and development. He often insisted to take into account embryonic and larval characters, most often using as examples his favourite animals, the cirripedes. Then I discuss remaining problems, and also perspectives, to address the link between phylogeny and development in the modern terms of molecular and cladistic phylogenetics and of molecular and genetic developmental biology.


Assuntos
Artrópodes/classificação , Artrópodes/crescimento & desenvolvimento , Evolução Biológica , Biologia do Desenvolvimento/história , Filogenia , Animais , Biologia do Desenvolvimento/tendências , História do Século XIX , História do Século XX , História do Século XXI
17.
Evol Dev ; 8(5): 433-45, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16925679

RESUMO

Females of the ants belonging to the queenless genus Diacamma have a pair of unique tiny thoracic appendages, called "gemmae," located on the mesothoracic segment. They are covered with sensory hairs, filled with exocrine glands and are involved in the behavioral regulation of reproduction. We report here a morphological, developmental, and genetic study of the development of the gemmae. Both male and female larvae have dorsal mesothoracic discs, although differing in shape and fate. In Diacamma ceylonense, we show that, contrary to butterflies, these discs specify parts of the adult thorax in addition to wing tissues, as in Drosophila. We have cloned and studied the expression of wingless (wg) and scalloped (sd), two genes known to play a critical role in wing morphogenesis in Drosophila. In the fly's mesothoracic dorsal disc, sd is specifically expressed in the wing pouch. In Diacamma, we show that sd is also expressed in male dorsal thoracic discs, whereas its expression was undetectable in females. From this result and observations of shape and growth of cultured isolated discs, we suggest that gemmae originate from a more ventral part of the dorsal disc than the wing pouch and discuss the pro and cons of gemma/wing homology.


Assuntos
Formigas/crescimento & desenvolvimento , Extremidades/anatomia & histologia , Proteínas de Insetos/genética , Animais , Formigas/anatomia & histologia , Formigas/genética , Padronização Corporal/genética , Padronização Corporal/fisiologia , Extremidades/crescimento & desenvolvimento , Feminino , Expressão Gênica , Proteínas de Insetos/metabolismo , Proteínas de Insetos/fisiologia , Larva/anatomia & histologia , Larva/crescimento & desenvolvimento , Larva/ultraestrutura , Masculino , Caracteres Sexuais , Tórax/embriologia , Tórax/crescimento & desenvolvimento , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/fisiologia , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteínas Wnt/fisiologia
18.
Dev Genes Evol ; 216(7-8): 431-42, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16773339

RESUMO

The remarkable diversity of form in arthropods reflects flexible genetic programs deploying many conserved genes. In the insect model Drosophila melanogaster, diversity of form can be observed between serially homologous appendages or when a single appendage is transformed by homeotic mutations, such as the adult labial mouthparts that can present alternative antennal, prothoracic, or maxillary identities. We have examined the roles of the Hox selector genes proboscipedia (pb) and Sex combs reduced (Scr), and the antennal selectors homothorax (hth) and spineless (ss) in labial specification, by tissue-directed mitotic recombination. Whereas loss of pb function transforms labium to prothoracic leg, loss of Scr, hth, or ss functions results in little or no change in labial specification. Results of analysis of single and multiple mutant combinations support a genetic hierarchy in which the homeotic pb gene possesses a primary role. It is surprising to note that while loss of ss activity alone had no detected effect, all mutant combinations lacking both pb and ss yielded the most severe phenotype observed: stunted, apparently tripartite legs that may correspond to a default state. The roles of the four selector genes are functionally linked to a cell nonautonomous mechanism involving the coupled activities of the decapentaplegic (dpp)/TGF-beta and wingless (wg)/Wnt signaling pathways. Accordingly, several mutant combinations impaired in dpp signaling were seen to reorient labial-to-leg transformations toward antennal aristae. A crucial aspect of selector function in development and evolution may be in regulating diffusible signals, including those emitted by dpp and wg.


Assuntos
Proteínas de Drosophila/fisiologia , Drosophila melanogaster/crescimento & desenvolvimento , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/fisiologia , Morfogênese/genética , Fatores de Transcrição/fisiologia , Animais , Artrópodes/genética , Artrópodes/crescimento & desenvolvimento , Proteínas de Drosophila/genética , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/genética , Proteínas de Homeodomínio/genética , Transdução de Sinais/genética , Fatores de Transcrição/genética
19.
Dev Genes Evol ; 216(7-8): 443-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16773337

RESUMO

The "hopeful monster" has haunted evolutionary thinking since Richard Goldschmidt coined the phrase in 1933. The phrase is directly related to genetic mechanisms in development and evolution. Cirripedes are peculiar crustaceans in that they all lack abdomens as adults. In a previous study aimed at describing the repertoire of Hox genes of the Cirripedia, we failed to isolate the abdominal-A gene in three species representative of all three cirripede orders. To address the question of whether the cirripede ancestor could have been a "hopeful monster" arising from a rearrangement of the Hox complex, we have performed a cytogenetic analysis of the Hox complex of the cirripede Sacculina carcini. We present here molecular and cytogenetic evidence for the grouping of the Hox genes on a single chromosome. This is the first direct evidence reported for the grouping of Hox genes on the same chromosome in a non-insect arthropod species.


Assuntos
Crustáceos/genética , Genes Homeobox , Família Multigênica , Animais , Passeio de Cromossomo , Cromossomos/genética , Hibridização in Situ Fluorescente , Cariotipagem
20.
Bioessays ; 27(7): 673-5, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15954097

RESUMO

In many bilaterian phyla, appendages are morphological traits that characterise the identity of the various body parts. In pterygote insects, wings are dorsal appendages on the thorax. The famous "bithorax" fly created by Ed Lewis is the emblematic example of the role of Hox genes.1 Now, Tomoyasu et al.,2 using classical genetics, transgenesis and RNAi, have examined the function of thoracic Hox genes in the beetle Tribolium castaneum. Beetles have rigid elytra in place of the first pair of wings. Instead of the expected transformation of the elytron into a wing, loss of Hox genes' function leads to the homeotic transformation of the second pair of dorsal appendages, the wings, into elytra. This has important consequences for the way that we see the role of Hox genes in development and evolution.


Assuntos
Proteínas de Homeodomínio/fisiologia , Tribolium/anatomia & histologia , Asas de Animais/fisiologia , Animais , Evolução Biológica , Borboletas , Linhagem da Célula , Besouros , Regulação da Expressão Gênica , Homeostase , Modelos Anatômicos , Modelos Biológicos , Interferência de RNA , Transgenes
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