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The development of somatic cells in to embryogenic cells occurs in several stages and ends in somatic embryo formation, though most of these biochemical and molecular changes have yet to be elucidated. Somatic embryogenesis coupled with genetic transformation could be a biotechnological tool to improve potential crop yields potential in sugarcane cultivars. The objective of this study was to observe somatic embryo development and to identify differentially expressed proteins in embryogenic (E) and non-embryogenic (NE) callus during maturation treatment. E and NE callus were cultured on maturation culture medium supplemented with different concentrations (0.0, 0.75, 1.5 and 2.0 g L-1) of activated charcoal (AC). Somatic embryo formation and differential protein expression were evaluated at days 0 and 21 using shotgun proteomic analyses. Treatment with 1.5 g L-1 AC resulted in higher somatic embryo maturation rates (158 somatic embryos in 14 days) in E callus but has no effect in NE callus. A total of 752 co-expressed proteins were identified through the SUCEST (The Sugarcane EST Project), including many housekeeping proteins. E callus showed 65 exclusive proteins on day 0, including dehydrogenase, desiccation-related protein, callose synthase 1 and nitric oxide synthase. After 21 days on maturation treatment, 14 exclusive proteins were identified in E callus, including catalase and secreted protein. NE callus showed 23 exclusive proteins on day 0 and 10 exclusive proteins after 21 days on maturation treatment, including many proteins related to protein degradation. The induction of maturation leads to somatic embryo development, which likely depends on the expression of specific proteins throughout the process, as seen in E callus under maturation treatment. On the other hand, some exclusive proteins can also specifically prevent of somatic embryos development, as seen in the NE callus. [ABSTRACT FROM AUTHOR]

Ethylene and polyamines (PAs) are two phytohormones that play important roles during in vitro morphogenesis of several plant species. The interaction between ethylene and PAs has been of interest because both have S-adenosylmethionine as a precursor. To study the influence of ethylene and PAs on in vitro morphogenesis of an ornamental pepper, we added an ethylene scavenger, PAs, a PA inhibitor, and compounds that affect ethylene biosynthesis and activity to the regeneration medium. Regeneration frequencies increased in response to treatment with ethylene inhibitors (aminoethoxyvinylglycine and silver thiosulfate) and an ethylene scavenger (mercury perchlorate). Treatment with the ethylene precursor 1-aminocyclopropane-1-carboxylic acid reduced the regeneration frequency, increased callus formation, and increased ethylene levels; similar results were obtained in response to treatment with the PA inhibitor methylglyoxal-bis(guanylhydrazone). By contrast, treatment with PAs (particularly spermidine and spermine) decreased ethylene levels, increased the regeneration frequency, and increased shoot bud formation. These results suggest a coordinated regulation of ethylene and polyamines because the suppression of ethylene levels using ethylene inhibitors, polyamines, or mercury perchlorate increased the in vitro regeneration frequency and morphogenic responses of Capsicum annuum L. [ABSTRACT FROM AUTHOR]

The Coffea arabica HB12 gene (CaHB12), which encodes a transcription factor belonging to the HD-Zip I subfamily, is upregulated under drought, and its constitutive overexpression (35S:CaHB12 OX ) improves the Arabidopsis thaliana tolerance to drought and salinity stresses. Herein, we generated transgenic cotton events constitutively overexpressing the CaHB12 gene, characterized these events based on their increased tolerance to water deficit, and exploited the gene expression level from the CaHB12 network. The segregating events Ev8.29.1, Ev8.90.1, and Ev23.36.1 showed higher photosynthetic yield and higher water use efficiency under severe water deficit and permanent wilting point conditions compared to wild-type plants. Under well-irrigated conditions, these three promising transformed events showed an equivalent level of Abscisic acid (ABA) and decreased Indole-3-acetic acid (IAA) accumulation, and a higher putrescine/(spermidine + spermine) ratio in leaf tissues was found in the progenies of at least two transgenic cotton events compared to non-transgenic plants. In addition, genes that are considered as modulated in the A. thaliana 35S:CaHB12 OX line were also shown to be modulated in several transgenic cotton events maintained under field capacity conditions. The upregulation of GhPP2C and GhSnRK2 in transgenic cotton events maintained under permanent wilting point conditions suggested that CaHB12 might act enhancing the ABA-dependent pathway. All these data confirmed that CaHB12 overexpression improved the tolerance to water deficit, and the transcriptional modulation of genes related to the ABA signaling pathway or downstream genes might enhance the defense responses to drought. The observed decrease in IAA levels indicates that CaHB12 overexpression can prevent leaf abscission in plants under or after stress. Thus, our findings provide new insights on CaHB12 gene and identify several promising cotton events for conducting field trials on water deficit tolerance and agronomic performance. • CaHB12 gene overexpression does not affect ABA hormone accumulation. • CaHB12 gene overexpression reduces IAA hormone accumulation in leaves. • CaHB12 gene overexpression increase putrescine/(spermidine + spermine) ratio in leaf tissues. • CaHB12 ox transgenic events showed a decrease in the IAA levels indicates that CaHB12 gene overexpression can prevent leaf abscission in plants under water deficit stress. • CaHB12 ox transgenic events showed improved tolerance to water deficit. [ABSTRACT FROM AUTHOR]

• Shiitake byproducts (stipes) are source of umami compounds for food application. • A valuing alternative for shiitake stipes use was developed. • Umami Ingredient is a likely option to low sodium food, helping flavor maintenance. An alternative use of shiitake stipes, usually treated as waste, was proposed for the production of a powder ingredient, rich in umami compounds, aiming its application in food. The extraction of umami compounds was optimized through the Response Surface Methodology (RSM), in order to obtain an extract with high umami taste intensity. From the optimized condition, a comparative analysis of shiitake stipes dehydration method was performed. Stipes were dehydrated by hot air drying (HD) and freeze drying (FD), submitted to extraction and the umami compounds in the extracts were compared. The comparative analysis showed that the 5′ - nucleotides are more sensitive to prolonged heating, while the release of free amino acids (FAA) was favored by hot air drying. The HD samples extract showed higher Equivalent Umami Concentration (EUC). The spray drying of the HD samples extract allowed the production of a newly powder ingredient rich in umami compounds (Umami Ingredient) that can be applied in diverse food matrices. Due to the presence of umami compounds, Umami Ingredient can be a potential alternative to help in the process of sodium reduction by enhancing food flavor. [ABSTRACT FROM AUTHOR]

• Solanum pimpinellifolium is susceptible to tomato mottle mosaic virus (ToMMV). • S. lycopersicum 'VFNT' was resistance to ToMMV. • Compatible interaction presented expressive changes in signaling molecules. • Responses activation on plant-virus interactions are timing-dependent. • NO and polyamines correlated negatively in S. pimpinellifolium -ToMMV plants. Plants are exposed to a vast array of pathogens. The interaction between them may be classified in compatible and incompatible. Polyamines (PAs) are involved in defense responses, as well as salicylic acid (SA), gentisic acid (GA) and nitric oxide (NO), which can increase the content of reactive oxygen species (ROS), creating a harsh environment to the pathogen. ROS can also damage the host cell and they can be controlled by ascorbate and glutathione. Among phytopathogens, one of the major threats to tomato crops is tomato mottle mosaic virus (ToMMV). Resistance against this virus probably involves the Tm-22 gene. This work aimed to analyze signaling and antioxidant molecules in the defense response against ToMMV in Solanum pimpinellifolium and in S. lycopersicum 'VFNT'. In S. pimpinellifolium plants inoculated with ToMMV, an increase in NO, SA, GA, ascorbate and oxidized glutathione and a decrease in the content of PAs were observed. Characteristic symptoms of diseased plants and high absorbance values in PTA-ELISA indicated a compatible interaction. In VFNT-inoculated plants, less significant differences were noticed. Symptoms and viral concentration were not detected, indicating an incompatible interaction, possibly associated with the effector-triggered immunity (ETI) response. [ABSTRACT FROM AUTHOR]