RESUMO
BACKGROUND: Hairy roots are a plant-tissue culture raised by Rhizobium rhizogenes infection (formerly known as Agrobacterium rhizogenes). Nowadays, these roots have been gaining more space in biotechnology due to their benefits for the recombinant expression of valuables proteins; it includes simplified downstream processing, protein rhizosecretion, and scalability in bioreactors. However, due to methodological inconsistency among reports, the tissue platform is still a promising technology. METHODS AND RESULTS: In the current paper, we propose the first step to overcome this issue through a systematic review of studies that employ Nicotiana hairy roots for recombinant expression. We conducted a qualitative synthesis of 36 out of 387 publications initially selected. Following the PRISMA procedure, all papers were assessed for exclusion and inclusion criteria. Multiple points of root culture were explored, including transformation methods, root growth curve, external additives, and scale-up with bioreactors to determine which approaches performed best and what is still required to achieve a robust protocol. CONCLUSION: The information presented here may help researchers who want to work with hairy roots in their laboratories trace a successful path to appraisal the literature status.
Assuntos
Biotecnologia , Nicotiana , Nicotiana/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Biotecnologia/métodos , Reatores Biológicos , Plantas Geneticamente Modificadas/genética , Raízes de Plantas/metabolismo , Transformação GenéticaRESUMO
The Somatic embryogenesis receptor-like kinase (SERK) gene plays an important role in plant somatic and zygotic embryogenesis induction. The gene encodes an LRR-containing receptor-like kinase protein. Studies have been carried out focusing on different aspects of its function, but definitive conclusions on its role are far from being reached. SERK expression is generally detected in cells in which somatic or zygotic embryogenesis has been triggered. Transgenic lettuce lines were produced to silence the endogenous SERK gene using antisense RNA. The average number of seeds per flower in the R(1) and R(2) generations was similar for both transgenic and non-transgenic lines. However, a reduction in the number of viable grained seeds was observed in four studied transgenic lines. Endogenous SERK expression analysis revealed the absence of detectable LsSERK gene transcripts in three transgenic lines, which presented a reduction in their ability to form in vitro somatic embryonic structures. In addition, transgenic lines showed enhanced susceptibility to the pathogenic fungus Sclerotinia sclerotiorum, when compared to control plants. The results support the idea that SERK genes might not only be involved in plant growth and development, but probably also in a general mechanism of biotic and abiotic stress perception.
Assuntos
Regulação da Expressão Gênica de Plantas , Genes de Plantas , Lactuca/genética , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas Quinases/genética , Sementes/embriologia , Ascomicetos/patogenicidade , Expressão Gênica , Lactuca/embriologia , Lactuca/microbiologia , Fenômenos Fisiológicos Vegetais/genética , Plantas Geneticamente Modificadas/fisiologia , Reação em Cadeia da Polimerase , Sementes/genética , Elementos Silenciadores Transcricionais , Transformação GenéticaRESUMO
Acca sellowiana has commercial potential due to the quality and the unique flavor of its fruit. Conservation of natural populations and management of breeding programmes would benefit from the availability of molecular markers that could be used to characterize levels and distribution of genetic variability. Thus, 13 microsatellite markers were developed from an enriched genomic library of A. sellowiana. They were characterized using 40 samples. The expected and observed heterozygosities ranged from 0.513 to 0.913 and from 0.200 to 0.889, respectively. These are the first microsatellite loci characterized from A. sellowiana that will contribute to improve researches on its genetic conservation, characterization and breeding.
RESUMO
Epidendrum puniceoluteum is an endemic orchid of Atlantic Rainforest, restricted to few populations only due to the destruction and fragmentation of its native habitat. Here, we report on the development of 10 microsatellite markers isolated from this orchid species. Genetic variability was characterized in two distant populations from Brazil coast. The number of alleles observed for each locus ranged from two to 12 and with an average of 6.4 alleles per locus. These microsatellites should be valuable tools for studying both fine-scale genetic structure of scattered E. puniceoluteum population and patterns will be useful genetic markers for other closely related taxa.
RESUMO
Acca sellowiana has commercial potential because of the quality and the unique flavor of its fruit. Conservation of natural populations and management of breeding programmes would benefit from the availability of molecular markers that could be used to characterize levels and distribution of genetic variability. Thus, 13 microsatellite markers were developed from an enriched genomic library of A. sellowiana. They were characterized using 40 samples. The expected and observed heterozygosities ranged from 0.513 to 0.913 and from 0.200 to 0.889, respectively. These are the first microsatellite loci characterized from A. sellowiana that will contribute to improve researches on the genetic conservation, characterization and breeding.
RESUMO
This article reviews recent results of studies aiming to elucidate modes of integrating signals initiated in ACTH receptors and FGF2 receptors, within the network system of signal transduction found in Y1 adrenocortical cells. These modes of signal integration should be central to the mechanisms underlying the regulation of the G0->G1->S transition in the adrenal cell cycle. FGF2 elicits a strong mitogenic response in G0/G1-arrested Y1 adrenocortical cells, that includes a) rapid and transient activation of extracellular signal-regulated kinases-mitogen-activated protein kinases (ERK-MAPK) (2 to 10 min), b) transcription activation of c-fos, c-jun and c-myc genes (10 to 30 min), c) induction of c-Fos and c-Myc proteins by 1 h and cyclin D1 protein by 5 h, and d) onset of DNA synthesis stimulation within 8 h. ACTH, itself a weak mitogen, interacts with FGF2 in a complex manner, blocking the FGF2 mitogenic response during the early and middle G1 phase, keeping ERK-MAPK activation and c-Fos and cyclin D1 induction at maximal levels, but post-transcriptionally inhibiting c-Myc expression. c-Fos and c-Jun proteins are mediators in both the strong and the weak mitogenic responses respectively triggered by FGF2 and ACTH. Induction of c-Fos and stimulation of DNA synthesis by ACTH are independent of PKA and are inhibited by the PKC inhibitor GF109203X. In addition, ACTH is a poor activator of ERK-MAPK, but c-Fos induction and DNA synthesis stimulation by ACTH are strongly inhibited by the inhibitor of MEK1 PD98059.
Assuntos
Humanos , Animais , Córtex Suprarrenal/citologia , Receptores da Corticotropina/fisiologia , Transdução de Sinais/fisiologia , Neoplasias do Córtex Suprarrenal , Ciclo Celular/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteína Quinase C/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Células Tumorais Cultivadas/fisiologiaRESUMO
This article reviews recent results of studies aiming to elucidate modes of integrating signals initiated in ACTH receptors and FGF2 receptors, within the network system of signal transduction found in Y1 adrenocortical cells. These modes of signal integration should be central to the mechanisms underlying the regulation of the G0-->G1-->S transition in the adrenal cell cycle. FGF2 elicits a strong mitogenic response in G0/G1-arrested Y1 adrenocortical cells, that includes a) rapid and transient activation of extracellular signal-regulated kinases-mitogen-activated protein kinases (ERK-MAPK) (2 to 10 min), b) transcription activation of c-fos, c-jun and c-myc genes (10 to 30 min), c) induction of c-Fos and c-Myc proteins by 1 h and cyclin D1 protein by 5 h, and d) onset of DNA synthesis stimulation within 8 h. ACTH, itself a weak mitogen, interacts with FGF2 in a complex manner, blocking the FGF2 mitogenic response during the early and middle G1 phase, keeping ERK-MAPK activation and c-Fos and cyclin D1 induction at maximal levels, but post-transcriptionally inhibiting c-Myc expression. c-Fos and c-Jun proteins are mediators in both the strong and the weak mitogenic responses respectively triggered by FGF2 and ACTH. Induction of c-Fos and stimulation of DNA synthesis by ACTH are independent of PKA and are inhibited by the PKC inhibitor GF109203X. In addition, ACTH is a poor activator of ERK-MAPK, but c-Fos induction and DNA synthesis stimulation by ACTH are strongly inhibited by the inhibitor of MEK1 PD98059.
Assuntos
Córtex Suprarrenal/citologia , Divisão Celular/fisiologia , Receptores da Corticotropina/fisiologia , Transdução de Sinais/fisiologia , Neoplasias do Córtex Suprarrenal , Animais , Ciclo Celular/fisiologia , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Proteína Quinase C/metabolismo , Receptores de Fatores de Crescimento de Fibroblastos/fisiologia , Células Tumorais Cultivadas/fisiologiaRESUMO
CA 15.3, a new tumor marker, is a glycoprotein antigen produced in greater amounts by breast tumor cells. It can be quantitatively detected, circulating in human serum or plasma, using an immunoradiometric assay with monoclonal antibodies. In order to evaluate the usefulness of the method and to determine the cut-off for metastatic disease, the CA 15.3 levels were determined in 78 patients (5 patients with breast fibroadenoma and 73 patients with breast cancer). The conclusions of the study are that the CA 15.3 is a useful parameter in the management of patients in different stages of the disease: levels above 36 U/ml are suggestive of metastasis, and above 86 U/ml are indicative of them. On the other hand, CA 15.3 does not seem to be helpful in the pre-operative differential diagnosis of breast lumps.