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MAIN CONCLUSION: An exonuclease V homologue from apomictic Brachiaria brizantha is expressed and localized in nucellar cells at key moments when these cells differentiate to give rise to unreduced gametophytes. Brachiaria is a genus of forage grasses with economical and agricultural importance to Brazil. Brachiaria reproduces by aposporic apomixis, in which unreduced embryo sacs, derived from nucellar cells, other than the megaspore mother cell (MMC), are formed. The unreduced embryo sacs produce an embryo without fertilization resulting in clones of the mother plant. Comparative gene expression analysis in ovaries of sexual and apomictic Brachiaria spp. revealed a sequence from B. brizantha that showed a distinct pattern of expression in ovaries of sexual and apomictic plants. In this work, we describe a gene named BbrizExoV with strong identity to exonuclease V (Exo V) genes from other grasses. Sequence analysis in signal prediction tools showed that BbrizExoV might have dual localization, depending on the translation point. A longer form to the nucleus and a shorter form which would be directed to the chloroplast. This is also the case for monocot sequences analyzed from other species. The long form of BbrizExoV protein localizes to the nucleus of onion epidermal cells. Analysis of ExoV proteins from dicot species, with exception of Arabidopsis thaliana ExoVL protein, showed only one localization. Using a template-based AlphaFold 2 modelling approach the structure of BbrizExoV in complex with metal and ssDNA was predicted based on the holo structure of the human counterpart. Features predicted to define ssDNA binding but a lack of sequence specificity are shared between the human enzyme and BbrizExoV. Expression analyses indicated the precise site and timing of transcript accumulation during ovule development, which coincides with the differentiation of nucelar cells to form the typical aposporic four-celled unreduced gametophyte. A putative function for this protein is proposed based on its homology and expression pattern.
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Apomixia , Arabidopsis , Brachiaria , Humanos , Exodesoxirribonuclease V , Gametogênese Vegetal , Células Germinativas Vegetais , PoaceaeRESUMO
Introduction: The pathophysiology of Chronic Rhinosinusitis is coordinated by distinct inflammatory reactions in different individuals. Inflammatory environments with a predominance of Th2 lymphocytes tend also to be rich in eosinophils. These environments are common during the formation of nasal polyps associated with aspirin intolerance, which is also marked by an increase in inflammatory mediators, especially IL-4, IL-5, and IL-13. Despite the significance of these inflammatory mediators, the relevance of IL-12 subunits' presence within eosinophilic nasal polyps, however, has been less studied. The current study aims to evaluate the presence of IL-12 subunits, IL-12p40 and IL-12p70, in eosinophilic nasal polyps and their correlations with IL-8 presence. Materials and Methods: We compared the concentrations of IL-8, IL12p40, and IL12p70 among samples of eosinophilic nasal polypoid tissue, eosinophilic nasal polypoid tissue associated with aspirin intolerance, and healthy nasal mucosa, using an indirect immunoassay (ELISA) kit. Results: When compared to healthy nasal mucosa, there was a lower concentration of IL-8 in Chronic Rhinosinusitis with Nasal Polyp (CRSwNP) tissue. Aspirin Intolerant polypoid tissue also presented a lower concentration of IL-12 subunits compared to healthy nasal mucosa. There was no significant correlation between IL-8 and IL-12 in the eosinophilic polypoid conditions. Conclusion: In CRSwNP, there is a reduction in IL-8 and IL-12 subunits compared to control, with a lack of correlation between IL-12 and IL-8. The lack of correlation can be justified by a type two inflammatory storm environment.
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Lecture capture (the real-time recording of live lectures) has become commonplace in higher education. It is popular with students who like the associated flexibility and believe that lecture recordings improve their grades. Here, we performed a survey (n = 694, 53% of the cohort) and set up focus groups (2 focus groups, 15 participants) to explore biological sciences students' perceptions of how lecture capture impacts their study behaviour when recordings are provided for every lecture and are made available to students without restriction. The participants in our study were convinced that lecture capture improved their learning, and many students noted that they were dependent on the recordings, thinking that without them, they would not be able to achieve good grades. Students reported that they spend a considerable amount of time watching recordings and making verbatim notes, leaving them little time for independent study. For many, lecture capture seems to reinforce the view that memorisation equals learning, a view that may be reinforced by knowledge-focussed assessment formats. For most students, lecture capture did not affect self-reported live lecture attendance patterns. However, about one-third of the participants reported skipping more classes, and the same participants were more likely to postpone catching up on missed lectures. The outcomes of our study suggest that lecture capture provision may negatively affect some students' attendance and study behaviour, and thus, we suggest more needs to be done to mitigate against this.
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Aprendizagem , Estudantes de Medicina , Humanos , Gravação em Vídeo , Currículo , Avaliação EducacionalRESUMO
OBJECTIVE: Some studies have pointed to gabapentinoids as promising medications in postoperative pain control. The objective of the present study was to evaluate the efficacy of pregabalin in reducing postoperative pain in tonsillectomy and lateral pharyngoplasties. STUDY DESIGN: Double-blind randomized controlled trial. SETTING: Tertiary care center. METHODS: A double-blind randomized controlled trial was conducted with patients undergoing tonsillectomies and lateral pharyngoplasties between Aug 29, 2017, and Oct 31, 2020. Data of interest such as opioid consumption, pain scores, and adverse outcomes such as dizziness, nausea, headache, and sedation within 7 days following surgeries were analyzed. RESULTS: No statistically significant difference was observed in pain scores and opioid consumption between the groups studied in the pilot project. The use of pregabalin was associated with lower incidence of dizziness compared to controls. CONCLUSION: Gabapentinoids, especially pregabalin, are drugs whose potential for controlling pain after pharyngeal surgery, such as tonsillectomy and sleep apnea surgery, still needs to be more fully evaluated. After the conclusion of the present study, we hope to answer this question about the role of pregabalin in oropharyngeal surgeries.
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Analgésicos , Tonsilectomia , Humanos , Pregabalina/uso terapêutico , Projetos Piloto , Analgésicos/uso terapêutico , Tonsilectomia/efeitos adversos , Analgésicos Opioides/uso terapêutico , Tontura/induzido quimicamente , Tontura/tratamento farmacológico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologiaRESUMO
The 4th joint UK Biochemical Society and Federation of European Biochemical Societies (FEBS) education event, 'Evolving Molecular Bioscience Education' took place online on May 27 and 28, 2021. The event, continuing the biennial series, comprised the invited speakers' talks, group discussions and other participants' pre-recorded flash presentations. Although the UK dominated, there were also speakers and participants from other European countries and other continents. This special issue includes a varied collection of articles written by the speakers and other participants.
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Bioquímica , HumanosRESUMO
Placements are often an extra-curricular activity of a science degree. This study reports on the outcomes of a final-year credit-bearing 6-week placement module that was specifically designed to develop and enhance students' employability skills. A key element of this module was that the student placements were not only evaluated from a science perspective, but also evaluated with an emphasis on meaningful reflection and evaluation of employability skills development. Students recorded their levels of confidence in skills before, during and after the placement via an Online Reflective Log, as part of a module's summative assessment. The results showed that taking part in the placement and conducting their own independent research helped students to make connections between their scientific knowledge, otherwise constrained within the walls of the undergraduate science laboratory, and the wider impact of their research on society. Another theme that emerged concerned career choices and aspirations, and the placement experiences either confirmed prior choices or opened new horizons. The Online Reflective Log helped students to feel supported by their university supervisor who were at a distance. Feedback on their tasks prompted students to reflect on the scientific and personal skills while being engaged in scientific activities during placement. Students agreed that they had further developed their employability skills during the placement and acknowledged that it was challenging to acquire evidence of skill development. However, students appreciated the usefulness of this reflection in relation to their future career development.
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Comunicação , Currículo , Ciência , Humanos , EstudantesRESUMO
[This corrects the article DOI: 10.1007/s12551-021-00887-6.].
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A longstanding challenge for educators in Higher Education is the need to prepare students for their career journey after graduation. While theoretical foundations are needed, students should be able to apply knowledge in new contexts and be able to demonstrate and evidence life- and employability-skills valuable to employers. Many degrees provide students with the opportunity to develop transferable skills, for instance through giving presentations and working in teams. Nevertheless, students are not always able to reflect on their skills development, and on the connection between theory, practice and their learning. Authentic assessments can create links between theory and practice preparing students for the workplace. However, it is common to see the product of a particular activity being assessed, and not the process through which the product was produced. This may encourage students to value the end product over skills development, and therefore not appreciate how their University experiences prepare them for the workplace. Science students can struggle with self-reflection, and therefore may find it difficult to articulate and evidence skills during job applications. We present different ways to foster self-reflection when transferable skills are embedded and assessed in the curriculum. However, we claim that the process of reflection should be taught and supported and new ways of assessing students are needed to help them develop their ability to self-reflect.
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Abstract Introduction: The real number of COVID-19 cases may be underestimated since several countries have difficulty offering laboratory tests for all the population. Therefore, finding a symptom with a high predictive value would help in diagnostic and isolation strategies. Objective: To correlate the sudden loss of the sense of smell in the context of the COVID-19 pandemic with results of diagnostic tests for COVID-19. Methods: This is a cross-sectional observational study. An online questionnaire was digitally addressed to 725 outpatients in Brazil who reported partial or total sudden loss of the sense of smell from March to April 2020. Results: Total or partial sudden loss of the sense of smell showed high positive predictive value for COVID-19 diagnosis, during the COVID-19 pandemic in Brazil (88.8%). There were no differences between groups tested positive and negative in regard to demographic and clinical characteristics such as presence of allergy, rhinitis, neither to olfactory recovery time. Conclusion: The identification of sudden loss of the sense of smell during COVID-19 pandemic may serve as a sentinel symptom and may be a warning to establish measures to prevent the transmission of the disease.
Resumo Introdução: O número real de casos Covid-19 pode estar subestimado, pois vários países têm dificuldade em oferecer exames laboratoriais para toda a população. Portanto, encontrar um sintoma com alto valor preditivo ajudaria nas estratégias de diagnóstico e isolamento. Objetivo: Correlacionar a perda súbita do olfato no contexto da pandemia da Covid-19 com os resultados dos testes de diagnóstico da Covid-19. Método: Trata-se de um estudo observacional transversal. Um questionário on-line foi enviado digitalmente a 725 voluntários que apresentaram perda súbita parcial ou total do sentido de olfato de março a abril de 2020 no Brasil. Resultados: A perda súbita total ou parcial do sentido do olfato apresentou alto valor preditivo positivo para o diagnóstico de Covid-19, durante a pandemia de Covid-19 no Brasil (88,8%). Não houve diferenças entre os grupos positivos e negativos em relação às características demográficas e clínicas, como presença de alergia, rinite e tempo de recuperação olfativa. Conclusão: A identificação de perda súbita do olfato durante a pandemia de Covid-19 pode servir como sintoma sentinela e pode ser um alerta para estabelecer medidas para impedir a transmissão da doença.
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Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Pneumonia Viral , Olfato , Infecções por Coronavirus , Pandemias , Betacoronavirus , Transtornos do Olfato , Brasil , Estudos TransversaisRESUMO
INTRODUCTION: The real number of COVID-19 cases may be underestimated since several countries have difficulty offering laboratory tests for all the population. Therefore, finding a symptom with a high predictive value would help in diagnostic and isolation strategies. OBJECTIVE: To correlate the sudden loss of the sense of smell in the context of the COVID-19 pandemic with results of diagnostic tests for COVID-19. METHODS: This is a cross-sectional observational study. An online questionnaire was digitally addressed to 725 outpatients in Brazil who reported partial or total sudden loss of the sense of smell from March to April 2020. RESULTS: Total or partial sudden loss of the sense of smell showed high positive predictive value for COVID-19 diagnosis, during the COVID-19 pandemic in Brazil (88.8%). There were no differences between groups tested positive and negative in regard to demographic and clinical characteristics such as presence of allergy, rhinitis, neither to olfactory recovery time. CONCLUSION: The identification of sudden loss of the sense of smell during COVID-19 pandemic may serve as a sentinel symptom and may be a warning to establish measures to prevent the transmission of the disease.
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Betacoronavirus , Infecções por Coronavirus , Transtornos do Olfato , Pandemias , Pneumonia Viral , Olfato , Adulto , Brasil , COVID-19 , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2RESUMO
Feedback can be an important element of learning, but only if students engage with it. Students are only likely to engage with feedback that they find useful. This study aimed to identify characteristics of written feedback perceived by students as effective. We used a mixed-method approach, integrating quantitative and qualitative data that were collected through the analysis of feedback that was identified by students as good, a student questionnaire, as well as interviews and a focus group exploring students' views on what good feedback looks like. Although the results show that length and composition of 'good' feedback can be extremely variable, some common characteristics could be identified, leading to a set of recommendations for staff marking written assessments. According to students, good feedback should be detailed and specific, and it should tell students how they can improve. Students also find it important that feedback is honest and constructive. In addition, positive reinforcement was identified as important by the focus group, although few examples of good written feedback on the assignment contained any direct praise. Surprisingly, feedforward which might help students in other modules did not feature highly in students' perceptions of good feedback, possibly indicating a focus by students on improving the current assignment rather than on future assignments.
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Educação/métodos , Avaliação Educacional/métodos , Estudantes/psicologia , Retroalimentação , Feminino , Grupos Focais , Humanos , Conhecimento Psicológico de Resultados , Aprendizagem , Masculino , Inquéritos e Questionários , Adulto JovemRESUMO
Teaching bioinformatics is a longstanding challenge for educators who need to demonstrate to students how skills developed in the classroom may be applied to real world research. This study employed an action research methodology which utilised student-staff partnership and peer-learning. It was centred on the experiences of peer-facilitators, students who had previously taken a postgraduate bioinformatics module, and had applied knowledge and skills gained from it to their own research. It aimed to demonstrate to peer-receivers, current students, how bioinformatics could be used in their own research while developing peer-facilitators' teaching and mentoring skills. This student-centred approach was well received by the peer-receivers, who claimed to have gained improved understanding of bioinformatics and its relevance to research. Equally, peer-facilitators also developed a better understanding of the subject and appreciated that the activity was a rare and invaluable opportunity to develop their teaching and mentoring skills, enhancing their employability.
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Different bioinformatics methods illuminate different aspects of protein function, from specific catalytic activities to broad functional categories. Here, a triple-pronged approach to predict function for a domain of unknown function, DUF2086, is applied. Distant homology to characterised enzymes and conservation of key residues suggest an oxygenase function. Modelling indicates that the substrate is most likely a nucleic acid. Finally, genomic context analysis linking DUF2086 to DNA repair, leads to a predicted activity of oxidative demethylation of damaged bases in DNA. The newly assigned activity is sporadically present in phyla not containing near relatives of the similarly active repair protein AlkB.
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Reparo do DNA , DNA Bacteriano/metabolismo , Proteínas de Escherichia coli/química , Escherichia coli/genética , Oxigenases de Função Mista/química , Shewanella/genética , Software , Sequência de Aminoácidos , Biologia Computacional/métodos , Dano ao DNA , DNA Bacteriano/genética , Escherichia coli/enzimologia , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Família Multigênica , Estrutura Terciária de Proteína , Alinhamento de Sequência , Shewanella/enzimologia , Homologia Estrutural de ProteínaRESUMO
BACKGROUND: The heterotrophic dinoflagellate Oxyrrhis marina is increasingly studied in experimental, ecological and evolutionary contexts. Its basal phylogenetic position within the dinoflagellates make O. marina useful for understanding the origin of numerous unusual features of the dinoflagellate lineage; its broad distribution has lent O. marina to the study of protist biogeography; and nutritive flexibility and eurytopy have made it a common lab rat for the investigation of physiological responses of marine heterotrophic flagellates. Nevertheless, genome-scale resources for O. marina are scarce. Here we present a 454-based transcriptome survey for this organism. In addition, we assess sequence read abundance, as a proxy for gene expression, in response to salinity, an environmental factor potentially important in determining O. marina spatial distributions. RESULTS: Sequencing generated ~57 Mbp of data which assembled into 7, 398 contigs. Approximately 24% of contigs were nominally identified by BLAST. A further clustering of contigs (at ≥ 90% identity) revealed 164 transcript variant clusters, the largest of which (Phosphoribosylaminoimidazole-succinocarboxamide synthase) was composed of 28 variants displaying predominately synonymous variation. In a genomic context, a sample of 5 different genes were demonstrated to occur as tandem repeats, separated by short (~200-340 bp) inter-genic regions. For HSP90 several intergenic variants were detected suggesting a potentially complex genomic arrangement. In response to salinity, analysis of 454 read abundance highlighted 9 and 20 genes over or under expressed at 50 PSU, respectively. However, 454 read abundance and subsequent qPCR validation did not correlate well - suggesting that measures of gene expression via ad hoc analysis of sequence read abundance require careful interpretation. CONCLUSION: Here we indicate that tandem gene arrangements and the occurrence of multiple transcribed gene variants are common and indicate potentially complex genomic arrangements in O. marina. Comparison of the reported data set with existing O. marina and other dinoflagellates ESTs indicates little sequence overlap likely as a result of the relatively limited extent of genome scale sequence data currently available for the dinoflagellates. This is one of the first 454-based transcriptome surveys of an ancestral dinoflagellate taxon and will undoubtedly prove useful for future comparative studies aimed at reconstructing the origin of novel features of the dinoflagellates.
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Dinoflagellida/genética , Salinidade , Transcriptoma , Sequência de Aminoácidos , Mapeamento de Sequências Contíguas , Dinoflagellida/classificação , Etiquetas de Sequências Expressas , Genoma , Proteínas de Choque Térmico HSP90/genética , Peptídeo Sintases/genética , Filogenia , Proteínas de Protozoários/genética , Alinhamento de Sequência , Análise de Sequência de DNARESUMO
The immunological environment experienced by parasitic nematodes varies greatly between hosts and is particularly influenced by whether or not a host has been previously infected. How a parasitic nematode responds to these different environments is poorly understood, but may allow a parasite to ameliorate the adverse effects of host immunity on parasite fitness. Here we use a microarray approach to identify genes in the parasitic nematode Strongyloides ratti that exhibit differential transcription between different rat host immunological environments, and between replicate lines of S. ratti selected for either early or late reproduction. We hypothesise that such genes may be used by this species to cope with and respond to its host environment. Our results showed that, despite large phenotypic differences between S. ratti adults from different immunological environments, the S. ratti transcriptome exhibited a relatively stable pattern of expression. Thus, differential expression amongst treatments was limited to a small proportion of transcripts and generally involved only modest fold changes. These transcripts included a group of collagen genes up-regulated in parasites early in an infection, and in immunised host environments, which may be related to protection against the damage caused to a parasite by host immune responses. We found that later in an infection, a number of genes associated with muscle function and repair were up-regulated in immunised host environments; these may help parasites maintain their position in the host intestine. Differences in transcription between selection lines of S. ratti were only observed in immunised hosts and included genes associated with the response to the host's immunological environment.
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Perfilação da Expressão Gênica , Interações Hospedeiro-Parasita , Strongyloides ratti/genética , Estrongiloidíase/imunologia , Animais , Feminino , Proteínas de Helminto/genética , Proteínas de Helminto/imunologia , Humanos , Dados de Sequência Molecular , Ratos , Strongyloides ratti/imunologia , Estrongiloidíase/parasitologiaRESUMO
Third-generation sequencing has given new impetus to protein sequence database growth, revealing new domains. Description and analysis of these is required to further improve the coverage and utility of domain databases. A novel domain, here named BACON, was discovered from analysis of metagenomic data obtained from gut bacteria. Domain architectures unambiguously link its function to carbohydrate metabolism but a further strong connection to protease domains suggests that many BACON domains bind glycoproteins. Conserved residues in the BACON domain are also characteristic of carbohydrate binding while its biased phyletic distribution and other data suggest mucin as a potential specific target.
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Bactérias/genética , Metagenômica/métodos , FilogeniaRESUMO
BACKGROUND: Aspartic proteases are known to play an important role in the biology of nematode parasitism. This role is best characterised in blood-feeding nematodes, where they digest haemoglobin, but they are also likely to play important roles in the biology of nematode parasites that do not feed on blood. In the present work, we investigate the evolution and expression of aspartic proteases in Strongyloides ratti, which permits a unique comparison between parasitic and free-living adult forms within its life-cycle. RESULTS: We identified eight transcribed aspartic protease sequences and a further two genomic sequences and compared these to homologues in Caenorhabditis elegans and other nematode species. Phylogenetic analysis demonstrated a complex pattern of gene evolution, such that some S. ratti sequences had a one-to-one correspondence with orthologues of C. elegans but that lineage-specific expansions have occurred for other aspartic proteases in these two nematodes. These gene duplication events may have contributed to the adaptation of the two species to their different lifestyles. Among the set of S. ratti aspartic proteases were two closely-related isoforms that showed differential expression during different life stages: ASP-2A is highly expressed in parasitic females while ASP-2B is predominantly found in free-living adults. Molecular modelling of the ASP-2 isoforms reveals that their substrate specificities are likely to be very similar, but that ASP-2B is more electrostatically negative over its entire molecular surface than ASP-2A. This characteristic may be related to different pH values of the environments in which these two isoforms operate. CONCLUSIONS: We have demonstrated that S. ratti provides a powerful model to explore the genetic adaptations associated with parasitic versus free-living life-styles. We have discovered gene duplication of aspartic protease genes in Strongyloides and identified a pair of paralogues differentially expressed in either the parasitic or the free-living phase of the nematode life-cycle, consistent with an adaptive role for aspartic proteases in the evolution of nematode parasitism.
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Ácido Aspártico Proteases/genética , Evolução Molecular , Proteínas de Helminto/genética , Strongyloides ratti/enzimologia , Sequência de Aminoácidos , Animais , Caenorhabditis elegans/genética , Hibridização Genômica Comparativa , DNA de Helmintos/genética , Feminino , Biblioteca Gênica , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Isoformas de Proteínas/genética , Estrutura Secundária de Proteína , Alinhamento de Sequência , Análise de Sequência de DNA , Strongyloides ratti/genética , Especificidade por SubstratoRESUMO
BACKGROUND: Sequence identification of ESTs from non-model species offers distinct challenges particularly when these species have duplicated genomes and when they are phylogenetically distant from sequenced model organisms. For the common carp, an environmental model of aquacultural interest, large numbers of ESTs remained unidentified using BLAST sequence alignment. We have used the expression profiles from large-scale microarray experiments to suggest gene identities. RESULTS: Expression profiles from approximation 700 cDNA microarrays describing responses of 7 major tissues to multiple environmental stressors were used to define a co-expression landscape. This was based on the Pearsons correlation coefficient relating each gene with all other genes, from which a network description provided clusters of highly correlated genes as 'mountains'. We show that these contain genes with known identities and genes with unknown identities, and that the correlation constitutes evidence of identity in the latter. This procedure has suggested identities to 522 of 2701 unknown carp ESTs sequences. We also discriminate several common carp genes and gene isoforms that were not discriminated by BLAST sequence alignment alone. Precision in identification was substantially improved by use of data from multiple tissues and treatments. CONCLUSION: The detailed analysis of co-expression landscapes is a sensitive technique for suggesting an identity for the large number of BLAST unidentified cDNAs generated in EST projects. It is capable of detecting even subtle changes in expression profiles, and thereby of distinguishing genes with a common BLAST identity into different identities. It benefits from the use of multiple treatments or contrasts, and from the large-scale microarray data.