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Sforca, D. A.

Publications and source records attributed to Sforca, D. A..

10 recordsLinked to original sources

Genetic response to light and carbon source variations in Trichoderma harzianum: The key regulatory roles of env1, cre1, and blr2

In filamentous fungi, light plays a key role in regulating physiological processes such as growth, conidiation, secondary metabolism, and the expression of hydrolytic enzymes. The processes that depend on light are controlled by photoreceptors, including BLR1, BLR2, and ENV1, as well as by signaling pathways involving heterotrimeric G-proteins and cyclic adenosine monophosphate (cAMP). Trichoderma harzianum is a promising candidate for biotechnological use and is able to promote hydrolytic reactions under biomass degradation conditions. However, the genetic mechanisms underlying its response to light remain poorly understood, especially under degradative conditions. This study aimed to assess the expression of carbohydrate-active enzymes (CAZymes), transcription factors (TFs), and signaling pathway proteins under different light conditions and carbon sources. The results revealed distinct patterns of relative gene expression influenced by these environmental factors, highlighting the complex regulatory mechanisms at play in T. harzianum. Moreover, our results suggested that env1, cre1, and blr2 are critical for adjusting to different light conditions and carbon sources. This highlights the importance of both factors in regulating gene expression and supporting metabolic adaptation in T. harzianum. To our knowledge, such findings have not been previously reported in the context of cellulose degradation for this species. Overall, these results offer valuable insights into how T. harzianum responds to environmental changes, revealing a complex regulatory network that is not only crucial for optimizing fungal growth in industrial applications but also deepens our understanding of its biology and ecological interactions. Highlights{blacksquare} Trichoderma harzianum is a key candidate for biotechnology applications. {blacksquare}Light and carbon control CAZymes, photoreceptors, key regulators, and signaling. {blacksquare}T. harzianum has distinct gene expression patterns under different light conditions and carbon sources. {blacksquare}env1, cre1, and blr2 regulate metabolic adaptation in T. harzianum. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=185 SRC="FIGDIR/small/657067v1_ufig1.gif" ALT="Figure 1"> View larger version (72K): org.highwire.dtl.DTLVardef@8167c7org.highwire.dtl.DTLVardef@1c46f6borg.highwire.dtl.DTLVardef@16eddc8org.highwire.dtl.DTLVardef@1a2afa6_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

Sugarcane yellow leaf virus impairs the transcriptomic defense responses of sugarcane to its new aphid vector Melanaphis sorghi

Sugarcane (Saccharum spp.) is a preeminent sugar and bioenergy crop and has great economic importance in tropical countries. A major disease affecting this crop is yellow leaf disease, which is caused by sugarcane yellow leaf virus (SCYLV, Polerovirus SCYLV, Solemoviridae). The sugarcane aphid Melanaphis sacchari is considered the main vector of SCYLV, and the closely related sorghum aphid Melanaphis sorghi, which has recently emerged as a pest of great relevance in sorghum, has also been suspected as a vector. Genetic resistance is an important resource for preventing yield losses caused by SCYLV and its vectors, but knowledge on the underlying molecular mechanisms is lacking. Therefore, the present work was aimed at investigating the transcriptomic responses of sugarcane to SCYLV and M. sorghi, which was reported to transmit this virus for the first time herein. Two sugarcane cultivars, one susceptible and one tolerant to SCYLV, were fed upon by aviruliferous and viruliferous aphids. The transcriptome of the plants was assessed by RNA-Seq using differential gene expression analyses and a gene coexpression network. The susceptible cultivar showed an incipient reaction to both M. sorghi and SCYLV, with very few differentially expressed genes (DEGs) identified in comparison with aphid-free plants. The response of the tolerant cultivar to aviruliferous M. sorghi involved pathways typically associated with defense against herbivory, which were also enriched in coexpression network modules in which DEGs were overrepresented. Some of these genes were hubs in their respective modules, indicating they are potential key regulators of the defense responses. However, these responses were diminished when viruliferous aphids were used, and other processes linked to infection with SCYLV were altered. These results indicated that SCYLV could affect sugarcane defense responses to its vector, similar to other viruses of the same genus. Some possible implications for the epidemiology and impact of SCYLV and M. sorghi are discussed.

plant biology↗

Identifying Candidate Genes for Sugar Accumulation in Sugarcane Cultivars: From a Syntenic Genomic Region to a Gene Coexpression Network

Elucidating the intricacies of the sugarcane genome is essential for breeding superior cultivars. This economically important crop originates from hybridizations of highly polyploid Saccharum species. However, the large size (10 Gb), high polyploidy, and aneuploidy of the sugarcane genome pose significant challenges to complete genome sequencing, assembly, and annotation. One successful strategy for identifying candidate genes linked to agronomic traits, particularly those associated with sugar accumulation, leverages synteny and potential collinearity with related species. In this study, we explored synteny between sorghum and sugarcane. Genes from a sorghum Brix QTL were used to screen bacterial artificial chromosome (BAC) libraries from two Brazilian sugarcane varieties (IACSP93-3046 and SP80-3280). The entire region was successfully recovered, confirming synteny and collinearity between the species. Manual annotation identified 51 genes in the hybrid varieties that were subsequently confirmed to be present in Saccharum spontaneum. To identify candidate genes for sugar accumulation, this study employed a multifaceted approach, including retrieving the genomic region of interest, performing gene-by-gene analysis, analyzing RNA-seq data of internodes from Saccharum officinarum and S. spontaneum accessions, constructing a coexpression network to examine the expression patterns of genes within the studied region and their neighbors, and finally identifying differentially expressed genes (DEGs). This comprehensive approach led to the discovery of three candidate genes potentially involved in sugar accumulation: an ethylene-responsive transcription factor (ERF), an ABA 8-hydroxylase, and a prolyl oligopeptidase (POP). These findings could be valuable for identifying additional candidate genes for other important agricultural traits and directly targeting candidate genes for further work in molecular breeding.

genomics↗

Lignocellulolytic carbohydrate-active enzyme-encoding gene clusters in novel Trichoderma atroviride and Trichoderma harzianum strains: A BAC-guided transcriptome analysis

Lignocellulosic biomass is known as a challenging substrate for enzymatic hydrolysis, increasing the processing cost in biorefineries. In nature, filamentous fungi, including those of the genus Trichoderma, naturally degrade lignocellulose by using an arsenal of hydrolytic and oxidative enzymes that act synergistically with biomass degradation. This work explored the genome organization of target genes of Trichoderma atroviride and Trichoderma harzianum that are able to promote hydrolysis by identifying regions enriched in degradative enzyme-encoding genes, namely, hydrolytic clusters. We employed bacterial artificial chromosome (BAC) methodology to target specific genomic regions to explore their genetic organization, proximal gene context, and gene expression under degradative conditions. Using this tool, it was possible to inspect the linear structure and expression data of target hydrolytic-rich genomic regions. The results offered a genomic perspective of the organization of genome regions related to carbohydrate metabolism, revealing novel genome regions and genes that are positively regulated during cellulose degradation and contributing to elucidating differences in gene organization among Trichoderma species. HighlightsO_LIHigh-quality genomic regions were selected using closely related species CAZyme targets. C_LIO_LIRNA-seq data were used to quantify BAC genes expression. C_LIO_LIRelevant regions were identified by combining functional and differential expression data. C_LIO_LINovel targets for future characterization identified via differential expression. C_LI

genomics↗

Taxonomically Restricted Genes are Associated with Responses to Biotic and Abiotic Stresses in Sugarcane (Saccharum spp.)

Orphan genes (OGs) are protein-coding genes that are restricted to particular clades or species and lack homology with genes from other organisms, making their biological function difficult to predict. OGs can rapidly originate and become functional; consequently, they may support rapid adaptation to environmental changes. Extensive spread of mobile elements, and whole genome duplication, occurred in the Saccharum group, which may have contributed to the origin and diversification of OGs in the sugarcane genome. Here, we identified and characterized OGs in sugarcane, examined their expression profiles across tissues and genotypes, and investigated their regulation under varying conditions. We identified 319 OGs in the Saccharum spontaneum genome without detected homology to protein-coding genes in green plants, except those belonging to Saccharinae. Transcriptomic analysis showed 288 sugarcane OGs with detectable expression levels in at least one tissue or genotype. We observed similar expression patterns of OGs in sugarcane genotypes originating from the closest geographical locations. We also observed tissue-specific expression of some OGs, possibly indicating a complex regulatory process for maintaining diverse functional activity of these genes across sugarcane tissues and genotypes. Sixty-six OGs were differentially expressed under stress conditions, especially cold and osmotic stresses. Gene co-expression network and functional enrichment analyses suggested that sugarcane OGs may be involved in several biological mechanisms, including stimulus response and defence mechanisms. These findings provide a valuable genomic resource for sugarcane researchers, especially those interested in selecting stress-responsive genes.

plant biology↗

Whole-Genome Sequencing and Comparative Genomic Analysis of Potential Biotechnological Strains from Trichoderma harzianum, Trichoderma atroviride, and Trichoderma reesei

Trichoderma atroviride and Trichoderma harzianum are widely used as commercial biocontrol agents against plant diseases. Recently, T. harzianum IOC-3844 (Th3844) and T. harzianum CBMAI-0179 (Th0179) demonstrated great potential in the enzymatic conversion of lignocellulose into fermentable sugars. Herein, we performed whole-genome sequencing and assembly of the Th3844 and Th0179 strains. To assess the genetic diversity within the genus Trichoderma, the results of both strains were compared with strains of T. atroviride CBMAI-00020 (Ta0020) and T. reesei CBMAI-0711 (Tr0711). The sequencing coverage value of all genomes evaluated in this study was higher than that of previously reported genomes for the same species of Trichoderma. The resulting assembly revealed total lengths of 40 Mb (Th3844), 39 Mb (Th0179), 36 Mb (Ta0020), and 32 Mb (Tr0711). A genome-wide phylogenetic analysis provided details on the relationships of the newly sequenced species with other Trichoderma species. Structural variants revealed genomic rearrangements among Th3844, Th0179, Ta0020, and Tr0711 relative to the T. reesei QM6a reference genome and showed the functional effects of such variants. In conclusion, the findings presented herein allow the visualization of genetic diversity in the evaluated strains and offer opportunities to explore such fungal genomes in future biotechnological and industrial applications.

genomics↗

Temporal Gene Expression in Apical Culms Shows Early Changes in Cell Wall Biosynthesis Genes in Sugarcane

Multiple genes in sugarcane control sucrose accumulation and the biosynthesis of cell wall components; however, it is unclear how these genes are expressed in its apical culms. To better understand this process, we sequenced mRNA from +1 stem internodes collected from four genotypes with different concentrations of soluble solids. Culms were collected at four different time points, ranging from six to 12-month-old plants. Here we show differentially expressed genes related to sucrose metabolism and cell wall biosynthesis, including genes encoding invertases, sucrose synthase and cellulose synthase. Our results showed increased expression of invertases in IN84-58, the genotype with lower sugar and higher fiber content, as well as delayed expression of secondary cell wall-related cellulose synthase for the other genotypes. Interestingly, genes involved with hormone metabolism were differentially expressed across time points in the three genotypes with higher soluble solids content. A similar result was observed for genes controlling maturation and transition to reproductive stages, possibly a result of selection against flowering in sugarcane breeding programs. These results indicate that carbon partitioning in apical culms of contrasting genotypes is mainly associated with differential cell wall biosynthesis, and may include early modifications for subsequent sucrose accumulation. Co-expression network analysis identified transcription factors related to growth and development, showing a probable time shift for carbon partitioning occurred in 10-month-old plants.

genomics↗

The sugarcane and sorghum kinomes: insights into evolutionary expansion and diversification

The protein kinase (PK) superfamily is one of the largest superfamilies in plants and is the core regulator of cellular signaling. Even considering this substantial importance, the kinomes of sugarcane and sorghum have not been profiled. Here we identified and profiled the complete kinomes of the polyploid Saccharum spontaneum (Ssp) and Sorghum bicolor (Sbi), a close diploid relative. The Sbi kinome was composed of 1,210 PKs; for Ssp, we identified 2,919 PKs when disregarding duplications and allelic copies, which were related to 1,345 representative gene models. The Ssp and Sbi PKs were grouped into 20 groups and 120 subfamilies and exhibited high compositional similarities and evolutionary divergences. By utilizing the collinearity between these species, this study offers insights about Sbi and Ssp speciation, PK differentiation and selection. We assessed the PK subfamily expression profiles via RNA-Seq, identifying significant similarities between Sbi and Ssp. Moreover, through coexpression networks, we inferred a core structure of kinase interactions with specific key elements. This study is the first to categorize the allele specificity of a kinome and provides a wide reservoir of molecular and genetic information, enhancing the understanding of the evolutionary history of Sbi and Ssp PKs. HighlightThis study describes the catalog of kinase gene family in Saccharum spontaneum and Sorghum bicolor, providing a reservoir of molecular features and expression patterns based on RNA-Seq and co-expression networks.

genomics↗

Integrative Genomic Analysis for the Bioprospection of Regulators and Accessory Enzymes Associated with Cellulose Degradation in a Filamentous Fungus (Trichoderma harzianum)

BackgroundUnveiling fungal genome structure and function reveals the potential biotechnological use of fungi. Trichoderma harzianum is a powerful CAZyme-producing fungus. We studied the genomic regions in T. harzianum IOC3844 containing CAZyme genes, transcription factors and transporters.\n\nResultsWe used bioinformatics tools to mine the T. harzianum genome for potential genomics, transcriptomics, and exoproteomics data and coexpression networks. The DNA was sequenced by PacBio SMRT technology for multi-omics data analysis and integration. In total, 1676 genes were annotated in the genomic regions analyzed; 222 were identified as CAZymes in T. harzianum IOC3844. When comparing transcriptome data under cellulose or glucose conditions, 114 genes were differentially expressed in cellulose, with 51 CAZymes. CLR2, a transcription factor physically and phylogenetically conserved in T. harzianum spp., was differentially expressed under cellulose conditions. The genes induced/repressed under cellulose conditions included those important for plant biomass degradation, including CIP2 of the CE15 family and a copper-dependent LPMO of the AA9 family.\n\nConclusionsOur results provide new insights into the relationship between genomic organization and hydrolytic enzyme expression and regulation in T. harzianum IOC3844. Our results can improve plant biomass degradation, which is fundamental for developing more efficient strains and/or enzymatic cocktails for the production of hydrolytic enzymes.

genomics↗

Genetic variation in a complex polyploid: unveiling the dynamic allelic features of sugarcane

BackgroundSugarcane (Saccharum spp.) is highly polyploid and aneuploid. Modern cultivars are derived from hybridization between S. officinarum and S. spontaneum. This combination results in a genome exhibiting variable ploidy among different loci, a huge genome size (approximately 10 Gb) and a high content of repetitive regions. Gene expression mechanisms are poorly understood in these cultivars. An approach using genomic, transcriptomic and genetic mapping can improve our knowledge of the behavior of genetics in sugarcane.\n\nResultsThe hypothetical HP600 and centromere protein C (CENP-C) genes from sugarcane were used to elucidate the allelic expression and genomic and genetic behavior of this complex polyploid. The genomically side-by-side genes HP600 and CENP-C were found in two different homeologous chromosome groups with ploidies of eight and ten. The first region (Region01) was a Sorghum bicolor ortholog with all haplotypes of HP600 and CENP- C expressed, but HP600 exhibited an unbalanced haplotype expression. The second region (Region02) was a scrambled sugarcane sequence formed from different noncollinear genes containing duplications of HP600 and CENP-C (paralogs). This duplication occurred before the Saccharum genus formation and after the separation of sorghum and sugarcane, resulting in a nonexpressed HP600 pseudogene and a recombined fusion version of CENP-C and orthologous gene Sobic.003G299500 with at least two chimerical gene haplotypes expressed. The genetic map construction supported the difficulty of mapping markers located in duplicated regions of complex polyploid genomes.\n\nConclusionAll these findings describe a low synteny region in sugarcane, formed by events occurring in all members of the Saccharum genus. Additionally, evidence of duplicated and truncate gene expression and the behavior of genetic markers in a duplicated region was found. Thus, we describe the complexity involved in sugarcane genetics and genomics and allelic dynamics, which can be useful for understanding the complex polyploid genome.

plant biology↗