Induction Stage Research Articles

Biochemical events during somatic embryogenesis in Coffea arabica L.

Several biochemical components associated with different stages of somatic embryogenesis in coffee (Coffea arabica L.) are investigated using foliar explants. Soluble sugar, starch, free amino acids and total proteins were extracted and quantified at different stages of somatic embryogenesis, such as foliar segments (initial explants), primary calluses, embryogenic calluses, globular embryos, torpedoes, cotyledonary embryos and mature fruit zygotic embryos. Total soluble sugar levels increased sixfold at the initial stages of somatic embryogenesis induction. During this period, total soluble sugar in the cultures contained approximately 99.3% glucose and fructose. At 67.4μg/mg MS, no significant changes were observed in total sugar content during the embryo's somatic maturation and regeneration. During this stage, total soluble sugar was composed of 60% sucrose. After primary callus formation, starch contents increased gradually until the culture's conclusion. Total free amino acids, particularly arginine, lysine, methionine, asparagine, glutamine and histidine, revealed a higher synthesis until the formation of the primary callus, after which they remain statistically constant up to the end of the process. During the induction of calluses, a gradual increase of total proteins occurred, which, in the differentiating and maturing of somatic embryos, did not differ statistically till the formation of a cotyledonary embryo, when rates decreased 21.8%.

A Dynamic Spatio‐Temporal Expression Pattern of FGFR Isoforms During Scleral Ossicle Development

Fibroblast growth factors (FGFs) are an important family of proteins that play several roles during early vertebrate development. The FGF ligands bind to their membrane bound receptors (FGFRs) and activate downstream signalling pathways. Although the role of FGFRs has been widely studied in the development of endochondral bones, little is known about their role in the development of neural crest derived intramembranous bones. Scleral ossicles are a ring of 13–15 neural crest derived intramembranous bones in the eye of the chicken (Gallus gallus) and have been identified as a model for intramembranous bone formation. These bones are induced by a corresponding ring of epithelial thickenings, the conjunctival papillae. Using whole mount in situ hybridization, the spatio‐temporal expression patterns of ‘b’ and ‘c’ isoforms of FGFRs1–3 were determined during the stages of conjunctival papillae (HH30–33) as well as scleral ossicle development (HH34–37). The expression of both ‘b’ and ‘c’ isoforms of FGFRs1–3 were observed during conjunctival papillae development and their downregulation was observed during the stages of scleral ossicle induction. ImageJ was further used to study changes in the intensity of expression and to give a more precise indication of the stages of downregulation for each gene. Additionally, although all FGFRs were expressed in the epithelium, only FGFRs 1c, 2c, 3b and 3c were observed in the mesenchyme. The dynamic spatio‐temporal expression pattern of the FGFR isoforms during conjunctival papillae development implicates several FGF ligands in conjunctival papillae induction. This research will further our understanding of the signalling pathways potentially involved in the scleral ossicle system. FGF signaling is likely to interact with the Bone Morphogenetic Protein and Hedgehog pathways, already identified to play a role in the scleral ossicle system.Support or Funding InformationThis research was funded by the Natural Sciences and Engineering Research Council of CanadaThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Gene expression analysis of human adipose tissue-derived stem cells during the initial steps of in vitro osteogenesis

Mesenchymal stem cells (MSCs) have been widely studied with regard to their potential use in cell therapy protocols and regenerative medicine. However, a better comprehension about the factors and molecular mechanisms driving cell differentiation is now mandatory to improve our chance to manipulate MSC behavior and to benefit future applications. In this work, we aimed to study gene regulatory networks at an early step of osteogenic differentiation. Therefore, we analyzed both the total mRNA and the mRNA fraction associated with polysomes on human adipose tissue-derived stem cells (hASCs) at 24 h of osteogenesis induction. The RNA-seq results evidenced that hASC fate is not compromised with osteogenesis at this time and that 21 days of continuous cell culture stimuli are necessary for full osteogenic differentiation of hASCs. Furthermore, early stages of osteogenesis induction involved gene regulation that was linked to the management of cell behavior in culture, such as the control of cell adhesion and proliferation. In conclusion, although discrete initial gene regulation related to osteogenesis occur, the first 24 h of induction is not sufficient to trigger and drive in vitro osteogenic differentiation of hASCs.

Enhanced degradation of antibiotic sulfamethoxazole by electrochemical activation of PDS using carbon anodes

In this study, electrochemical activation of peroxydisulfate (PDS) using carbon anodes including multi-walled carbon nannotube (MWCNT), graphite (GR), black carbon (BC) and granular activated carbon (GAC) for degradation of antibiotic sulfamethoxazole (SMX) was investigated for the first time. The degradation of SMX by electrochemical activation of PDS using carbon anodes showed dual kinetics: an induction stage followed by a quick decay stage. In the latter stage, the degradation rate of SMX by electrochemical activation of PDS using MWCNT, GR, BC and GAC anodes increased about 15–35 times of that by electrolysis alone and 30–130 times of that by carbon/PDS (without applying current). The results of degradation of radical probes (atrazine (ATZ) and nitrobenzene (NB)) and radical scavenging effect manifest that nonradical oxidation, hydroxyl radical (HO) and sulfate radical (SO4−) jointly contributed to the degradation of SMX in electrochemical activation of PDS. The formation of transition state structure of PDS (activated PDS, PDS∗) between PDS molecule and carbon anodes by applying current was proposed to be responsible for nonradical oxidation, and its further decomposition resulted in the generation of HO and SO4−. Increasing PDS concentration (0.1–5 mM) or current density (10–200 A m−2) considerably promoted the degradation of SMX. Additionally, electrochemical activation of PDS using carbon anodes exhibited good resistance to water matrices.

Somatic embryogenesis, biochemical alterations and synthetic seed development in two varieties of coriander (Coriandrum sativum L.)

Somatic embryogenesis (SE), biochemical alterations and synthetic seed formation were carried out in two Coriandrum sativum L. varieties (Rajendra Swathi ‘RS’ and Co-1). Callus was induced profusely in 1.0 mg/l 2,4-dichlorophenoxy acetic acid (2,4-D) added MS medium but Co-1 had more callus induction frequency (96.0%) compared to RS (89.3%). The callus turned into embryogenic tissue and variable embryogenic frequency (77.6% in RS and 72.8% in Co-1) was noted. Somatic embryos started to differentiate on the same 2,4-D added medium but the numbers of somatic embryos were more in RS (63.0 embryos per culture) compared to Co-1 (51.0 embryos per culture). These somatic embryos progressed well and showed maximum maturation in RS (78.7%) in 0.25 mg/l 6-benzyl adenine (BA) + 0.5 mg/l α-naphthalene acetic acid (NAA) added medium. The biochemical analyses of non-embryogenic-, embryogenic-callus and different stages of embryos were conducted in order to know the changes of physiology in different tissues. Sugar and proline content were noted to be high at embryo induction stage while protein level was higher at embryo maturation stage. Biochemical analysis also revealed that the catalase (CAT) and superoxide dismutase (SOD) activities were higher at maturation stage of embryos compared to other embryogenic stages. Matured somatic embryos were germinated in MS added with 1.0 mg/l BA + 0.5 mg/l gibberellic acid (GA3) in which 83.3% and 76.7% plantlet regeneration were noticed in RS and Co-1 respectively. Somatic embryos were encapsulated in various alginate and calcium chloride (CaCl2) solutions and were kept in different temperature regimes for varied periods. On regeneration medium, the encapsulated embryos germinated into plantlets; in 3% sodium alginate + 100 mM CaCl2, maximum plant regeneration (74.0% in RS and 70.6% in Co-1) was noted. The influence of low temperature on storage of synthetic seeds and their conversion into plantlets were also studied and we noted that the 4°C was the optimum temperature for synthetic seed conservation and plantlet regeneration compared to -20°C and 25oC temperature conditions.

Outcomes of oral lichen planus and oral lichenoid lesions treated with topical corticosteroid.

To determine corticosteroid treatment effectiveness in patients with oral lichen planus/oral lichenoid lesions (OLP/OLL). Twenty-one patients with OLP and eighty-one patients with OLL received 0.05% clobetasol propionate (CP) or 0.05% triamcinolone acetonide (TA) in aqueous solution (AS) or orabase (OB), evaluating responses to treatment and follow-up compliance. Lesions were atrophic (72 of 102; 70.6%), extensive (58 of 100; 58%), producing eating difficulties (62 of 102; 60.8%), and spontaneous pain (30 of 102; 29.4%); 50 patients (49%) received CP-AS. The mean±SD percentage of follow-ups attended was 43±32%. Symptom remission was achieved in 46% of patients receiving CP-AS, 36.36% of those receiving TA-AS, 20% of those receiving CP-OB, and 25% of those receiving TA-OB. Follow-up compliance was poor in 66.7% of patients. Among 51 patients with continuous symptoms, 64.7% evidenced total remission at treatment completion; among 33 with intermittent symptoms, 73.1% had outbreaks 2-3times/year and 51.5% controlled outbreaks with <6 corticosteroid applications. Adverse effects were observed in seven patients (6.8%) (moon face, hirsutism, capillary fragility) in induction stage, subsiding with dose; among 15 patients under maintenance treatment for >6months, one showed hypothalamic-pituitary-adrenal (HPA) axis inhibition but not adrenal insufficiency. Our treatment proved highly effective and safe. Recall programs are desirable to enhance follow-up compliance.

Human dental stem cell derived transgene-free iPSCs generate functional neurons via embryoid body-mediated and direct induction methods.

Induced pluripotent stem cells (iPSCs) give rise to neural stem/progenitor cells, serving as a good source for neural regeneration. Here, we established transgene-free (TF) iPSCs from dental stem cells (DSCs) and determined their capacity to differentiate into functional neurons in vitro. Generated TF iPSCs from stem cells of apical papilla and dental pulp stem cells underwent two methods-embryoid body-mediated and direct induction, to guide TF-DSC iPSCs along with H9 or H9 Syn-GFP (human embryonic stem cells) into functional neurons in vitro. Using the embryoid body-mediated method, early stage neural markers PAX6, SOX1, and nestin were detected by immunocytofluorescence or reverse transcription-real time polymerase chain reaction (RT-qPCR). At late stage of neural induction measured at Weeks 7 and 9, the expression levels of neuron-specific markers Nav1.6, Kv1.4, Kv4.2, synapsin, SNAP25, PSD95, GAD67, GAP43, and NSE varied between stem cells of apical papilla iPSCs and H9. For direct induction method, iPSCs were directly induced into neural stem/progenitor cells and guided to become neuron-like cells. The direct method, while simpler, showed cell detachment and death during the differentiation process. At early stage, PAX6, SOX1 and nestin were detected. At late stage of differentiation, all five genes tested, nestin, βIII-tubulin, neurofilament medium chain, GFAP, and Nav, were positive in many cells in cultures. Both differentiation methods led to neuron-like cells in cultures exhibiting sodium and potassium currents, action potential, or spontaneous excitatory postsynaptic potential. Thus, TF-DSC iPSCs are capable of undergoing guided neurogenic differentiation into functional neurons in vitro, thereby may serve as a cell source for neural regeneration.

Biology and development of galls induced by Lopesia sp. (Diptera: Cecidomyiidae) on leaves of Mimosa gemmulata (Leguminosae: Caesalpinioideae)

Analyses of gall biology and development allow determination of morphogenesis events in host-plant organs that are altered by galling insects. Currently, we assume that there is a correlation between Lopesia sp. instars and the alterations in gall tissues on Mimosa gemmulata that generate the gall shape. The development of Lopesia sp. (three larval instars, pupae and adult) correlates positively with gall growth, especially on the anticlinal axis. First-instar larvae are found in galls at the stage of induction, Instar 2 in galls at early growth and development, Instar 3 in galls at late growth and development, pupae in galls at maturation, and the adult emerges from senescent galls. At induction, the larva stimulates cell differentiation in pinnula and pinna-rachis tissues on M. gemmulata. At early growth and development stages, cell division and expansion are increased, and non-glandular trichomes assist gall closing. Homogenous parenchyma and neoformed vascular bundles characterise late growth and development. At maturation, tissues are compartmentalised and cells achieve major expansion through elongation. At senescence, galls open by the falling of trichomes, and mechanical and nutritive cells have thickened walls. The neoformed nutritive tissue nurtures the developing Lopesia sp., whose feeding behaviour influences the direction of cell elongation, predominantly periclinal, determinant for gall bivalve shape.

Pertumbuhan dan Perkembangan Jaringan Meristem Bawang Merah (Allium ascalonicum L.) Kultivar Katumi Secara In Vitro

This study aimed for knowing and obtaining the best concentration of kinetin and NAA interaction effects in influencing the shoot induction, knowing how the plant growth regulators in induction mediastill affect the shoot additionin the MS0media and also knowing the largest number of roots in rooting media for shallot by in vitro. The experiment was conducted at Laboratory of Tissue Culture Seed Technology, Faculty of Agriculture, Padjadjaran University, during January 2011 until May 2011. This experiment divided in 3 stages, namely shoot induction stage, shoot subculture to MS0 media stage and shoot subculture to rooting media stage. Experimental method used in the shoot induction stage was factorial Completely Randomized Design with three replications. The first factor was the kinetin with four levels,0, 1, 2, and 3 mg L-1. The second factor was the NAA with three levels, as 0, 0.01, and 0.1 mg L-1. Basic media used for each treatment was MS. The experiment result showed there was an interaction between kinetin and NAA on shoot induction stagewith the plantlet height, leaf number, and shoot addition. The best result for leaf number was gained from interaction with 2 mg L-1 kinetin without NAA,while the treatment of 2 mg L-1 kinetin with 0.01 mg L-1 NAA gave a better interaction for theshoot addition variable.

Influence of triacontanol and jasmonic acid on metabolomics during early stages of root induction in cultured tissue of tomato (Lycopersicon esculentum)

Influence of n-triacontanol (TRIA) and jasmonic acid (JA) on metabolic profiling during root morphogenesis was studied in Lycopersicon esculentum (cv. PKM-1). Proton nuclear magnetic resonance (1H NMR) based metabolomics was employed to investigate the variations in metabolic profile. Chenomx NMR suite v.8.1 was used to identify and quantify metabolites based on their respective signature spectra. The levels of 47 metabolites were monitored for 72 h at specific time intervals (0, 3, 6, 9, 12, 24, 36, 48 and 72 h). Principal component analysis was performed to determine the variations in the metabolic profile between control and treatments during in vitro rhizogenesis. TRIA was observed to promote early root emergence (24 h) and also influence the metabolic variation during rhizogenesis between 9 and 24 h post exposure. Compounds such as IAA, ATP, NADPH, UDP-N-acetylglucosamine and gallate predominated at 9 h. Unlike TRIA, JA was unable to promote an early root induction. However, it influenced the synthesis of a relatively higher concentration of IAA at 6 h when compared to ATP, NADPH and trigonelline at 9 h. In the presence of both TRIA and JA (TRIA + JA), significant changes in the metabolic profiles were observed 24 h post exposure and the rooting was observed only after 72 h. The study suggests that TRIA may accelerate in vitro rhizogenesis of cultured tomato tissues by mainly increasing the synthesis of other growth promoting metabolites. But in the presence of JA, TRIA’s effect appears to be reduced.

Effectiveness of clove oil as an Anesthetic on Mozambique tilapia (Oreochromis mossambicus)

Anesthesia in aquaculture is generally used during sampling, weighing, disease diagnosis and transportation. Total 99 fish (mean length 6.55 cm±0.04; mean weight 3.64 g±0.05) were used for this experiment. This experiment was carried out in triplicate using ten different concentration of clove oil (10, 20, 30, 40, 50, 60, 70, 80, 90, 100 mg/l) along with control (without clove oil). For the experiment, 1 litre tanks were used as induction tank and 10 litre tanks were used as recovery tank. Clove oil is not soluble in water so stock solution was prepared using absolute ethanol in the ratio of 1:10 before experiment and directly added to induction tank and induction time was measured. The fish werethen transferred to recovery tank and three different stages of recovery were measured. Clove oil concentration 10 mg/l did not produce any stage of anesthesia while 20 mg/l produced only two stages of induction and recovery. As the concentration of clove oil increased from 30 mg/l to 100 mg/l, time of induction decreased and time of recovery increased. 100 mg/l was found to be an ideal concentration as it produced induction in less than 3 min. The result of this experiment suggested that clove oil can be used as an effective anesthetic on tilapia which produced minimum stress without mortality.

Comprehensive analysis of GASA family members in the Malus domestica genome: identification, characterization, and their expressions in response to apple flower induction

BackgroundThe plant-specific gibberellic acid stimulated Arabidopsis (GASA) gene family is critical for plant development. However, little is known about these genes, particularly in fruit tree species.ResultsWe identified 15 putative Arabidopsis thaliana GASA (AtGASA) and 26 apple GASA (MdGASA) genes. The identified genes were then characterized (e.g., chromosomal location, structure, and evolutionary relationships). All of the identified A. thaliana and apple GASA proteins included a conserved GASA domain and exhibited similar characteristics. Specifically, the MdGASA expression levels in various tissues and organs were analyzed based on an online gene expression profile and by qRT-PCR. These genes were more highly expressed in the leaves, buds, and fruits compared with the seeds, roots, and seedlings. MdGASA genes were also responsive to gibberellic acid (GA3) and abscisic acid treatments. Additionally, transcriptome sequencing results revealed seven potential flowering-related MdGASA genes. We analyzed the expression levels of these genes in response to flowering-related treatments (GA3, 6-benzylaminopurine, and sugar) and in apple varieties that differed in terms of flowering (‘Nagafu No. 2’ and ‘Yanfu No. 6’) during the flower induction period. These candidate MdGASA genes exhibited diverse expression patterns. The expression levels of six MdGASA genes were inhibited by GA3, while the expression of one gene was up-regulated. Additionally, there were expression-level differences induced by the 6-benzylaminopurine and sugar treatments during the flower induction stage, as well as in the different flowering varieties.ConclusionThis study represents the first comprehensive investigation of the A. thaliana and apple GASA gene families. Our data may provide useful clues for future studies and may support the hypotheses regarding the role of GASA proteins during the flower induction stage in fruit tree species.

Loneliness, personal and social well-being: towards a conceptualization of the effects of cyberbullying / Soledad, bienestar social e individual: hacia una conceptualización de los efectos del cyberbullying

This paper examines the effects of cyberbullying using a mixed method approach, by combining interviews, focus groups and a survey of 7,000 students. In the inductive stage, and following an axial coding analysis, we identified 153 concepts related to conflicts, which were divided into three thematic units to explain the greater impact of cyberbullying: (1) social distance; (2) privacy exposure; and (3) range of the material. The survey concluded that: (1) the victims of bullying and cyberbullying present higher levels of loneliness and lower levels of social well-being compared to non-bullied students, and those who were bullied in both channels presented higher levels of loneliness and lower levels of social well-being than those who were bullied in only one of them; (2) the victims of cyberbullying showed lower levels of individual well-being compared with those who had never been bullied, as with those who suffered face-to-face bullying. This difference was explained by testimonies indicating that most of the cyberbullying was related to intimate content, which has a higher impact on image perception.

Numerical Investigation on Flame Stabilization in DLR Hydrogen Supersonic Combustor with Strut Injection

ABSTRACTFlame stabilization in the DLR hydrogen supersonic combustor with strut injection was numerically investigated by using an in-house large eddy simulation code developed on the OpenFoam platform. To facilitate the comparison and analysis of various hydrogen oxidation mechanisms with different levels of mechanism reduction, the proposed 2D calculation model was validated against both the 3D simulation and the experimental data. The results show that the 2D model can capture the DLR flow and combustion characteristics with satisfactorily quantitative accuracy and significantly less computational load. By virtue of the flow visualization and the analyses of species evolution and heat release, the supersonic combustion in the DLR combustor can be divided into three stages along the streamwise direction: the induction stage where ignition occurs and active radicals are produced, the transition stage through which radicals are advected to the downstream, and the intense combustion stage where most heat release occurs. Furthermore, the sensitivity analysis of key reaction steps identifies the important role of chain carrying and heat release reactions in numerically reproducing the three-stage combustion stabilization mode in the DLR combustor.

CD146 coordinates brain endothelial cell–pericyte communication for blood–brain barrier development

The blood-brain barrier (BBB) establishes a protective interface between the central neuronal system and peripheral blood circulation and is crucial for homeostasis of the CNS. BBB formation starts when the endothelial cells (ECs) invade the CNS and pericytes are recruited to the nascent vessels during embryogenesis. Despite the essential function of pericyte-EC interaction during BBB development, the molecular mechanisms coordinating the pericyte-EC behavior and communication remain incompletely understood. Here, we report a single cell receptor, CD146, that presents dynamic expression patterns in the cerebrovasculature at the stages of BBB induction and maturation, coordinates the interplay of ECs and pericytes, and orchestrates BBB development spatiotemporally. In mouse brain, CD146 is first expressed in the cerebrovascular ECs of immature capillaries without pericyte coverage; with increased coverage of pericytes, CD146 could only be detected in pericytes, but not in cerebrovascular ECs. Specific deletion of Cd146 in mice ECs resulted in reduced brain endothelial claudin-5 expression and BBB breakdown. By analyzing mice with specific deletion of Cd146 in pericytes, which have defects in pericyte coverage and BBB integrity, we demonstrate that CD146 functions as a coreceptor of PDGF receptor-β to mediate pericyte recruitment to cerebrovascular ECs. Moreover, we found that the attached pericytes in turn down-regulate endothelial CD146 by secreting TGF-β1 to promote further BBB maturation. These results reveal that the dynamic expression of CD146 controls the behavior of ECs and pericytes, thereby coordinating the formation of a mature and stable BBB.

Comparative Transcriptome Analysis of SE initial dedifferentiation in cotton of different SE capability

Somatic embryogenesis (SE) is a critical transition from vegetative to embryogenic growth in higher plants; however, few studies have investigated the mechanism that regulates SE initial differentiation. Most cotton varieties have not undergone regeneration by SE, so only a few varieties can be used in genetic engineering. Here, two varieties of cotton with different SE capabilities (HD, higher differentiation and LD, lower differentiation) were analyzed by high throughout RNA-Seq at the pre-induction stage (0h) and two induction stages (3h and 3d) under callus-induction medium (CIM). About 1150 million clean reads were obtained from 98.21% raw data. Transcriptomic analysis revealed that “protein kinase activity” and “oxidoreductase activity” were highly represented GO terms during the same and different treatment stages among HD and LD. Moreover, several stress-related transcription factors might play important roles in SE initiation. The SE-related regulation genes (SERKs) showed different expression patterns between HD and LD. Furthermore, the complex auxin and ethylene signaling pathway contributes to initiation of differentiation in SE. Thus, our RNA-sequencing of comparative transcriptome analysis will lay a foundation for future studies to better define early somatic formation in cotton with different SE capabilities.

Perioperative airway management for pediatric anesthesia

Due to the characteristics of anatomy and physiology, children might experience more risk of respiratory complications than adults.We provided some skills and strategies for the three stages of anesthesia including preoperative assessment, anesthesia induction and maintenance and post-anesthesia recovery to optimize the perioperative airway management of pediatric anesthesia.Preoperative airway evaluations, anesthesia induction methods and corresponding airway management modalities, the common airway adverse events and their prevention and treatment were described in detail. Key words: Intraoperative period; Child; Intraoperative complications

Characteristics of Enthusiastic and Growing School-Based Agricultural Education Teachers: A Delphi Approach

The most optimal way to prepare teachers is a source of debate and inquiry. The common view held in school-based agricultural education is to use professional development to augment what teachers learned in their teacher preparation program. This has been typically implemented through induction support and generic professional development. Fessler and Christensen (1992) described a teacher career cycle that highlights the need to differentiate professional development for teachers beyond the induction stage. Teachers in the Enthusiastic and Growing stage are described as having a high level of competence, but continue to grow as professionals. The purpose of this study was to determine the characteristics of Enthusiastic and Growing school-based agriculture education teachers in order to inform professional development practice. A panel of 105 Enthusiastic and Growing teachers were selected to serve on a Delphi panel and asked to identify the characteristics of an expert agriculture teacher. Twenty-seven responses were agreed upon by the panel. Some characteristics were congruent with the existing descriptions of Enthusiastic and Growing teachers, while some descriptions were unique to school-based agricultural education. Based on these findings, professional development should be implemented using a systems approach to promote these characteristics in teachers.

Comparison of methods for obtaining doubled haploids of carrot

Doubled haploid lines of carrot can be obtained through androgenesis in anther cultures and in isolated microspore cultures. The two methods were compared using three carrot cultivars (‘Kazan F1’, ‘Feria F1’, and ‘Narbonne F1’) at the androgenesis induction stage, during plant regeneration from embryos, and during acclimatization of androgenetic plants as well as their characterization. It was found that cultivar was the main factor affecting the efficiency at each stage of plant production in both anther and isolated microspore cultures. The efficiency of androgenesis in anther cultures of ‘Feria F1’ was considerably higher in comparison with isolated microspore cultures, and more plants were obtained from the embryos of androgenesis-cultured plants. In ‘Kazan F1’ and ‘Narbonne F1’, more acclimatized androgenetic plants were produced from anther cultures. Ploidy assessment of acclimatized plants of ‘Narbonne F1’ showed that the majority of the plants in the population derived from anther cultures had a doubled chromosome (DH) set. On the other hand, the majority of plants obtained from isolated microspore cultures were haploids. When assessing homozygosity, it was found among plants obtained in anther cultures that the percentage of homozygotes for phosphoglucose isomerase (PGI) and aspartate aminotransferase (AAT) depended on the cultivar. In contrast, the majority of plants derived from isolated microspore cultures were homozygous regardless of cultivar.

Genome-wide identification, evolution, and expression analysis of GATA transcription factors in apple (Malus × domestica Borkh.)

Plant GATA transcription factors are type-IV zinc-finger proteins that play important regulatory roles in plant growth and development. In this study, we identified 35 GATA genes classified into four groups in the whole genome sequence of Malus domestica. A physiochemical property analysis indicated that GATA proteins are largely unstable hydrophilic proteins. An analysis of conserved protein motifs uncovered three highly conserved motifs, in addition to the GATA motif, in all MdGATA proteins. These three motifs, CCT, TIFY, and ASXH, were found to occur in specific GATA groups and may be related to GATA gene function. We identified 10 pairs of putative paralogs, indicating that MdGATA genes have mainly undergone whole genome duplication. Eighteen orthologous gene pairs were also identified between Arabidopsis thaliana and M. domestica. Furthermore, many light-responsive cis-elements were found in MdGATA gene promoters. Tissue-specific expression analysis performed by quantitative real-time reverse transcription PCR showed that MdGATA genes were preferentially expressed in flowers, leaves, and buds. Apple seedlings maintained in darkness for 7days exhibited a moderate decline in chlorophyll content along with significant down-regulation of most MdGATA genes, suggesting that MdGATA genes may be involved in light-responsive development and chlorophyll-level regulation. The distinctly higher expression levels observed for many MdGATA genes during three stages of floral induction also indicate that MdGATA genes may play a role in the apple flowering transition. The results presented here lay the foundation for further investigation of MdGATA gene family putative functions and improvement of apple yields.