A berinjela é uma espécie solanácea não tuberosa de importância agronômica, cultivada principalmente por seus frutos. Na medicina popular, a berinjela é indicada para o tratamento de várias doenças, incluindo diabetes, artrite, asma e bronquite. A berinjela é suscetível a várias doenças e pragas que causam perdas econômicas significativas. Esse problema tem sido abordado com técnicas convencionais de melhoramento, utilizando espécies silvestres resistentes de Solanum, que possuem uma grande diversidade genética e são fontes de genes de interesse agronômico. A aplicação de metodologias in vitro à berinjela tem resultado em sucesso considerável. Os tecidos de berinjela apresentam um alto potencial morfogenético, sendo úteis para estudos de desenvolvimento e para o estabelecimento de abordagens biotecnológicas para a produção de variedades melhoradas, tais como o resgate de embriões, a seleção in vitro, a hibridização somática e a transformação genética. O conjunto dessas características também torna a berinjela um modelo completo para estudos em diferentes áreas de pesquisa, incluindo o controle da expressão gênica e a avaliação da estabilidade de somaclones derivados de diferentes processos morfogenéticos. Neste trabalho, são analisados fatores importantes que afetam a eficiência dos processos de regeneração in vitro por meio de organogênese e embriogênese, assim como de transformação genética, explorando ainda o potencial da espécie como planta modelo para o estudo de vários aspectos da genética e fisiologia vegetais.

Eggplant is an agronomically important non-tuberous solanaceous crop grown primarily for its large oval fruit. In popular medicine, eggplant is indicated for the treatment of several diseases, including diabetes, arthritis, asthma and bronchitis. Eggplant is susceptible to a number of diseases and pests capable of causing serious crop losses. This problem has been addressed by hybridizing eggplant with wild resistant Solanum species, which present a wide genetic diversity and are source of useful agronomic traits. The application of in vitro methodologies to eggplant has resulted in considerable success. Eggplant tissues present a high morphogenetic potential that is useful for developmental studies as well as for establishing biotechnological approaches to produce improved varieties, such as embryo rescue, in vitro selection, somatic hybridization and genetic transformation. Taken together, these characteristics also make eggplant a complete model for studies on different areas of plant science, including control of gene expression and assessment of genetic stability of somaclones derived from different morphogenetic processes. In the present study, important factors that affect the efficiency of in vitro regeneration through organogenesis and embryogenesis as well as genetic transformation are analyzed. The potential of this species as a model plant for studying various aspects of plant genetics and physiology is also discussed.

The occurrence of quasi-repetitive glycine-rich peptides has been reported in different organisms. Glycine-rich regions are proposed to be involved in protein-protein interactions in some mammalian protein families. In plants, a set of glycine-rich proteins (GRPs) was characterized several years ago, and since then a wealth of new GRPs have been identified. GRPs may have very diverse sub-cellular localization and functions. The only common feature among all different GRPs is the presence of glycine-rich repeat domains. The expression of genes encoding GRPs is developmentally regulated, and also induced, in several plant genera, by physical, chemical and biological factors. In addition to the highly modulated expression, several GRPs also show tissue-specific localization. GRPs specifically expressed in xylem, phloem, epidermis, anther tapetum and roots have been described. In this paper, the structural and functional features of these proteins in Eucalyptus are summarized. Since this is the first description of GRPs in this species, particular emphasis has been given to the expression pattern of these genes by analyzing their abundance and prevalence in the different cDNA-libraries of the Eucalyptus Genome Sequencing Project Consortium (ForEST). The comparison of GRPs from Eucalyptus and other species is also discussed.

A embriogênese somática em berinjela foi induzida a partir de explantes cotiledonares cultivados em meio MS suplementado com 54 µM de ANA. A análise anatômica do início de formação e desenvolvimento de embriões somáticos foi realizada durante as primeiras quatro semanas. A formação de pré-embriões foi observada após o segundo dia de cultura, diretamente a partir de células perivasculares ou a partir de massas pré-embriogênicas derivadas de massas meristemáticas indeterminadas (IMMs) formadas a partir do tecido vascular. As IMMs também deram origem a primórdios radiculares após 10 dias de cultura. A origem dos embriões é discutida, assim como as similaridades entre a formação de embriões somáticos e raízes adventícias.

Somatic embryogenesis was induced from cotyledon explants of eggplant cultured on MS medium supplemented with 54 µM NAA. Anatomical analysis of somatic embryo initiation and development was performed during the first four weeks. Proembryo formation was observed after the second day of culture, directly from perivascular cells or via pro-embryogenic masses derived from indeterminate meristematic masses (IMMs) originated in the vascular tissue. Those IMMs also gave rise to root primordia after 10 days of culture. The origin of embryos is discussed as well as the similarities between somatic embryogenesis and adventitious root formation.

The expression of AtchitIV gene was analysed in Arabidopsis plants submitted to abiotic stresses. Transcript accumulation was detected in leaves in response to UV light exposure, exogenous salicylic acid administration and wounding. Transgenic Arabidopsis plants carrying AtchitIV promoter::gus fusion also showed differential expression of the reporter gene in response to these treatments. The AtchitIV expression was also analysed during Arabidopsis embryo development. GUS assay demonstrated AtchitIV promoter activation in zygotic embryos from torpedo stage up to full maturation. Promoter deletion analysis indicated that all the 5' cis-acting elements responsible for the specific tissue expression are located in a region of 1083 bp, adjacent to the start of transcription. A negative regulatory region located between portions -1083 and -600 was also observed.