The Experts below are selected from a list of 6219 Experts worldwide ranked by ideXlab platform
Joseph G. Dubrovsky - One of the best experts on this subject based on the ideXlab platform.
-
Transcriptomics insights into the genetic regulation of root apical meristem exhaustion and determinate primary root growth in Pachycereus pringlei (Cactaceae)
Scientific Reports, 2018Co-Authors: Gustavo Rodriguez-alonso, Joseph G. Dubrovsky, Selene Napsucialy-mendivil, Marta Matvienko, Mayra L. López-valle, Pedro E. Lázaro-mixteco, Svetlana ShishkovaAbstract:Many Cactaceae species exhibit determinate growth of the primary root as a consequence of root apical meristem (RAM) exhaustion. The genetic regulation of this growth pattern is unknown. Here, we de novo assembled and annotated the root apex transcriptome of the Pachycereus pringlei primary root at three developmental stages, with active or exhausted RAM. The assembled transcriptome is robust and comprehensive, and was used to infer a transcriptional regulatory network of the primary root apex. Putative orthologues of Arabidopsis regulators of RAM maintenance, as well as putative lineage-specific transcripts were identified. The transcriptome revealed putative orthologues of most proteins involved in housekeeping processes, hormone signalling, and metabolic pathways. Our results suggest that specific transcriptional programs operate in the root apex at specific developmental time points. Moreover, the transcriptional state of the P . pringlei root apex as the RAM becomes exhausted is comparable to the transcriptional state of cells from the meristematic, elongation, and differentiation zones of Arabidopsis roots along the root axis. We suggest that the transcriptional program underlying the drought stress response is induced during Cactaceae root development, and that lineage-specific transcripts could contribute to RAM exhaustion in Cactaceae.
-
Determinate primary root growth as an adaptation to aridity in Cactaceae: towards an understanding of the evolution and genetic control of the trait
Annals of botany, 2013Co-Authors: Svetlana Shishkova, María Laura Las Peñas, Selene Napsucialy-mendivil, Marta Matvienko, Alexander Kozik, Jesús Montiel, Anallely Patiño, Joseph G. DubrovskyAbstract:†Background and Aims Species of Cactaceae are well adapted to arid habitats. Determinate growth of the primary root, which involves early and complete root apical meristem (RAM) exhaustion and differentiation of cells at the root tip, has been reported for some Cactoideae species as a root adaptation to aridity. In this study, the primary root growth patterns of Cactaceae taxa from diverse habitats are classified as being determinate or indeterminate, and the molecular mechanisms underlying RAM maintenance in Cactaceae are explored. Genes that were induced in the primary root of Stenocereus gummosus before RAM exhaustion are identified. †Methods Primary root growth was analysed in Cactaceae seedlings cultivated in vertically oriented Petri dishes. Differentially expressed transcripts were identified after reverse northern blots of clones from a suppression subtractive hybridization cDNA library. †KeyResults All species analysed from six tribes of the Cactoideae subfamily that inhabit arid and semi-arid regions exhibited determinate primary root growth. However, species from the Hylocereeae tribe, which inhabit mesic regions, exhibited mostly indeterminate primary root growth. Preliminary results suggest that seedlings of members of the Opuntioideae subfamily have mostly determinate primary root growth, whereas those of the Maihuenioideae and Pereskioideae subfamilies have mostly indeterminate primary root growth. Seven selected transcripts encoding homologues of heat stress transcription factor B4, histone deacetylase, fibrillarin, phosphoethanolamine methyltransferase, cytochrome P450 and gibberellin-regulated protein were upregulated inS.gummosus root tips during the initial growth phase. †Conclusions Primary root growth in Cactoideae species matches their environment. The data imply that determinate growth of the primary root became fixed after separation of the Cactiodeae/Opuntioideae and Maihuenioideae/ Pereskioideae lineages, and that the genetic regulation of RAM maintenance and its loss in Cactaceae is orchestrated by genes involved in the regulation of gene expression, signalling, and redox and hormonal responses.
-
Regeneration of roots from callus reveals stability of the developmental program for determinate root growth in Sonoran Desert Cactaceae
Plant Cell Reports, 2007Co-Authors: Svetlana Shishkova, Edith García-mendoza, Vicente Castillo-díaz, Norma E. Moreno, Jesús Arellano, Joseph G. DubrovskyAbstract:In some Sonoran Desert Cactaceae the primary root has a determinate root growth: the cells of the root apical meristem undergo only a few cell division cycles and then differentiate. The determinate growth of primary roots in Cactaceae was found in plants cultivated under various growth conditions, and could not be reverted by any treatment tested. The mechanisms involved in root meristem maintenance and determinate root growth in plants remain poorly understood. In this study, we have shown that roots regenerated from the callus of two Cactaceae species, Stenocereus gummosus and Ferocactus peninsulae , have a determinate growth pattern, similar to that of the primary root. To demonstrate this, a protocol for root regeneration from callus was established. The determinate growth pattern of roots regenerated from callus suggests that the program of root development is very stable in these species. These findings will permit future analysis of the role of certain Cactaceae genes in the determinate pattern of root growth via the regeneration of transgenic roots from transformed calli.
-
Developmental programmed cell death in primary roots of Sonoran Desert Cactaceae.
American journal of botany, 2005Co-Authors: Svetlana Shishkova, Joseph G. DubrovskyAbstract:Primary roots of two species of Sonoran Desert Cactaceae, Stenocereus gummosusand Pachycereus pringlei, have a determinate pattern of growth: meristematic cells divide only for a limited time and then differentiate. Detecting DNA fragmentation by terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL), we have shown that programmed cell death (PCD) was not involved in meristem exhaustion. However, we found TUNEL-positive nuclei in the root hair and root cap cells of both species. Programmed cell death in root hair cells has not been previously reported, and the pattern of PCD events in the root cap differed from that described earlier. These data suggest that in the studied Cactaceae, PCD is involved in developmental adaptations related to the formation of a compact root system important for rapid seedling establishment in a desert environment. Participation of PCD in developmental loss of the root cap and in root hair renovation proposed in the current study implicates an evolutionary conserved link between PCD and differentiation processes in plants.
Svetlana Shishkova - One of the best experts on this subject based on the ideXlab platform.
-
Transcriptomics insights into the genetic regulation of root apical meristem exhaustion and determinate primary root growth in Pachycereus pringlei (Cactaceae)
Scientific Reports, 2018Co-Authors: Gustavo Rodriguez-alonso, Joseph G. Dubrovsky, Selene Napsucialy-mendivil, Marta Matvienko, Mayra L. López-valle, Pedro E. Lázaro-mixteco, Svetlana ShishkovaAbstract:Many Cactaceae species exhibit determinate growth of the primary root as a consequence of root apical meristem (RAM) exhaustion. The genetic regulation of this growth pattern is unknown. Here, we de novo assembled and annotated the root apex transcriptome of the Pachycereus pringlei primary root at three developmental stages, with active or exhausted RAM. The assembled transcriptome is robust and comprehensive, and was used to infer a transcriptional regulatory network of the primary root apex. Putative orthologues of Arabidopsis regulators of RAM maintenance, as well as putative lineage-specific transcripts were identified. The transcriptome revealed putative orthologues of most proteins involved in housekeeping processes, hormone signalling, and metabolic pathways. Our results suggest that specific transcriptional programs operate in the root apex at specific developmental time points. Moreover, the transcriptional state of the P . pringlei root apex as the RAM becomes exhausted is comparable to the transcriptional state of cells from the meristematic, elongation, and differentiation zones of Arabidopsis roots along the root axis. We suggest that the transcriptional program underlying the drought stress response is induced during Cactaceae root development, and that lineage-specific transcripts could contribute to RAM exhaustion in Cactaceae.
-
Expression of the KNOTTED HOMEOBOX Genes in the Cactaceae Cambial Zone Suggests Their Involvement in Wood Development.
Frontiers in plant science, 2017Co-Authors: Jorge Reyes-rivera, Svetlana Shishkova, Gustavo Rodriguez-alonso, Emilio Petrone, Alejandra Vasco, Francisco Vergara-silva, Teresa TerrazasAbstract:The vascular cambium is a lateral meristem that produces secondary xylem (i.e., wood) and phloem. Different Cactaceae species develop different types of secondary xylem; however, little is known about the mechanisms underlying wood formation in the Cactaceae. The KNOTTED HOMEOBOX (KNOX) gene family encodes transcription factors that regulate plant development. The role of class I KNOX genes in the regulation of the shoot apical meristem, inflorescence architecture, and secondary growth is established in a few model species, while the functions of class II KNOX genes are less well understood, although the Arabidopsis thaliana class II KNOX protein KNAT7 is known to regulate secondary cell wall biosynthesis. To explore the involvement of the KNOX genes in the enormous variability of wood in Cactaceae, we identified orthologous genes expressed in species with fibrous (Pereskia lychnidiflora and Pilosocereus alensis), nonfibrous (Ariocarpus retusus), and dimorphic (Ferocactus pilosus) wood. Both class I and class II KNOX genes were expressed in the cactus cambial zone, including one or two class I paralogs of KNAT1, as well as one or two class II paralogs of KNAT3-KNAT4-KNAT5. While the KNOX gene SHOOTMERISTEMLESS (STM) and its ortholog ARK1 are expressed during secondary growth in the Arabidopsis and Populus stem, respectively, we did not find STM orthologs in the Cactaceae cambial zone, which suggests possible differences in the vascular cambium genetic regulatory network in these species. Importantly, while two class II KNOX paralogs from the KNAT7 clade were expressed in the cambial zone of A. retusus and F. pilosus, we did not detect KNAT7 ortholog expression in the cambial zone of P. lychnidiflora. Differences in the transcriptional repressor activity of secondary cell wall biosynthesis by the KNAT7 orthologs could therefore explain the differences in wood development in the cactus species.
-
Determinate primary root growth as an adaptation to aridity in Cactaceae: towards an understanding of the evolution and genetic control of the trait
Annals of botany, 2013Co-Authors: Svetlana Shishkova, María Laura Las Peñas, Selene Napsucialy-mendivil, Marta Matvienko, Alexander Kozik, Jesús Montiel, Anallely Patiño, Joseph G. DubrovskyAbstract:†Background and Aims Species of Cactaceae are well adapted to arid habitats. Determinate growth of the primary root, which involves early and complete root apical meristem (RAM) exhaustion and differentiation of cells at the root tip, has been reported for some Cactoideae species as a root adaptation to aridity. In this study, the primary root growth patterns of Cactaceae taxa from diverse habitats are classified as being determinate or indeterminate, and the molecular mechanisms underlying RAM maintenance in Cactaceae are explored. Genes that were induced in the primary root of Stenocereus gummosus before RAM exhaustion are identified. †Methods Primary root growth was analysed in Cactaceae seedlings cultivated in vertically oriented Petri dishes. Differentially expressed transcripts were identified after reverse northern blots of clones from a suppression subtractive hybridization cDNA library. †KeyResults All species analysed from six tribes of the Cactoideae subfamily that inhabit arid and semi-arid regions exhibited determinate primary root growth. However, species from the Hylocereeae tribe, which inhabit mesic regions, exhibited mostly indeterminate primary root growth. Preliminary results suggest that seedlings of members of the Opuntioideae subfamily have mostly determinate primary root growth, whereas those of the Maihuenioideae and Pereskioideae subfamilies have mostly indeterminate primary root growth. Seven selected transcripts encoding homologues of heat stress transcription factor B4, histone deacetylase, fibrillarin, phosphoethanolamine methyltransferase, cytochrome P450 and gibberellin-regulated protein were upregulated inS.gummosus root tips during the initial growth phase. †Conclusions Primary root growth in Cactoideae species matches their environment. The data imply that determinate growth of the primary root became fixed after separation of the Cactiodeae/Opuntioideae and Maihuenioideae/ Pereskioideae lineages, and that the genetic regulation of RAM maintenance and its loss in Cactaceae is orchestrated by genes involved in the regulation of gene expression, signalling, and redox and hormonal responses.
-
Regeneration of roots from callus reveals stability of the developmental program for determinate root growth in Sonoran Desert Cactaceae
Plant Cell Reports, 2007Co-Authors: Svetlana Shishkova, Edith García-mendoza, Vicente Castillo-díaz, Norma E. Moreno, Jesús Arellano, Joseph G. DubrovskyAbstract:In some Sonoran Desert Cactaceae the primary root has a determinate root growth: the cells of the root apical meristem undergo only a few cell division cycles and then differentiate. The determinate growth of primary roots in Cactaceae was found in plants cultivated under various growth conditions, and could not be reverted by any treatment tested. The mechanisms involved in root meristem maintenance and determinate root growth in plants remain poorly understood. In this study, we have shown that roots regenerated from the callus of two Cactaceae species, Stenocereus gummosus and Ferocactus peninsulae , have a determinate growth pattern, similar to that of the primary root. To demonstrate this, a protocol for root regeneration from callus was established. The determinate growth pattern of roots regenerated from callus suggests that the program of root development is very stable in these species. These findings will permit future analysis of the role of certain Cactaceae genes in the determinate pattern of root growth via the regeneration of transgenic roots from transformed calli.
-
Developmental programmed cell death in primary roots of Sonoran Desert Cactaceae.
American journal of botany, 2005Co-Authors: Svetlana Shishkova, Joseph G. DubrovskyAbstract:Primary roots of two species of Sonoran Desert Cactaceae, Stenocereus gummosusand Pachycereus pringlei, have a determinate pattern of growth: meristematic cells divide only for a limited time and then differentiate. Detecting DNA fragmentation by terminal deoxynucleotide transferase-mediated dUTP nick-end labeling (TUNEL), we have shown that programmed cell death (PCD) was not involved in meristem exhaustion. However, we found TUNEL-positive nuclei in the root hair and root cap cells of both species. Programmed cell death in root hair cells has not been previously reported, and the pattern of PCD events in the root cap differed from that described earlier. These data suggest that in the studied Cactaceae, PCD is involved in developmental adaptations related to the formation of a compact root system important for rapid seedling establishment in a desert environment. Participation of PCD in developmental loss of the root cap and in root hair renovation proposed in the current study implicates an evolutionary conserved link between PCD and differentiation processes in plants.
Selene Napsucialy-mendivil - One of the best experts on this subject based on the ideXlab platform.
-
Transcriptomics insights into the genetic regulation of root apical meristem exhaustion and determinate primary root growth in Pachycereus pringlei (Cactaceae)
Scientific Reports, 2018Co-Authors: Gustavo Rodriguez-alonso, Joseph G. Dubrovsky, Selene Napsucialy-mendivil, Marta Matvienko, Mayra L. López-valle, Pedro E. Lázaro-mixteco, Svetlana ShishkovaAbstract:Many Cactaceae species exhibit determinate growth of the primary root as a consequence of root apical meristem (RAM) exhaustion. The genetic regulation of this growth pattern is unknown. Here, we de novo assembled and annotated the root apex transcriptome of the Pachycereus pringlei primary root at three developmental stages, with active or exhausted RAM. The assembled transcriptome is robust and comprehensive, and was used to infer a transcriptional regulatory network of the primary root apex. Putative orthologues of Arabidopsis regulators of RAM maintenance, as well as putative lineage-specific transcripts were identified. The transcriptome revealed putative orthologues of most proteins involved in housekeeping processes, hormone signalling, and metabolic pathways. Our results suggest that specific transcriptional programs operate in the root apex at specific developmental time points. Moreover, the transcriptional state of the P . pringlei root apex as the RAM becomes exhausted is comparable to the transcriptional state of cells from the meristematic, elongation, and differentiation zones of Arabidopsis roots along the root axis. We suggest that the transcriptional program underlying the drought stress response is induced during Cactaceae root development, and that lineage-specific transcripts could contribute to RAM exhaustion in Cactaceae.
-
Determinate primary root growth as an adaptation to aridity in Cactaceae: towards an understanding of the evolution and genetic control of the trait
Annals of botany, 2013Co-Authors: Svetlana Shishkova, María Laura Las Peñas, Selene Napsucialy-mendivil, Marta Matvienko, Alexander Kozik, Jesús Montiel, Anallely Patiño, Joseph G. DubrovskyAbstract:†Background and Aims Species of Cactaceae are well adapted to arid habitats. Determinate growth of the primary root, which involves early and complete root apical meristem (RAM) exhaustion and differentiation of cells at the root tip, has been reported for some Cactoideae species as a root adaptation to aridity. In this study, the primary root growth patterns of Cactaceae taxa from diverse habitats are classified as being determinate or indeterminate, and the molecular mechanisms underlying RAM maintenance in Cactaceae are explored. Genes that were induced in the primary root of Stenocereus gummosus before RAM exhaustion are identified. †Methods Primary root growth was analysed in Cactaceae seedlings cultivated in vertically oriented Petri dishes. Differentially expressed transcripts were identified after reverse northern blots of clones from a suppression subtractive hybridization cDNA library. †KeyResults All species analysed from six tribes of the Cactoideae subfamily that inhabit arid and semi-arid regions exhibited determinate primary root growth. However, species from the Hylocereeae tribe, which inhabit mesic regions, exhibited mostly indeterminate primary root growth. Preliminary results suggest that seedlings of members of the Opuntioideae subfamily have mostly determinate primary root growth, whereas those of the Maihuenioideae and Pereskioideae subfamilies have mostly indeterminate primary root growth. Seven selected transcripts encoding homologues of heat stress transcription factor B4, histone deacetylase, fibrillarin, phosphoethanolamine methyltransferase, cytochrome P450 and gibberellin-regulated protein were upregulated inS.gummosus root tips during the initial growth phase. †Conclusions Primary root growth in Cactoideae species matches their environment. The data imply that determinate growth of the primary root became fixed after separation of the Cactiodeae/Opuntioideae and Maihuenioideae/ Pereskioideae lineages, and that the genetic regulation of RAM maintenance and its loss in Cactaceae is orchestrated by genes involved in the regulation of gene expression, signalling, and redox and hormonal responses.
Marta Matvienko - One of the best experts on this subject based on the ideXlab platform.
-
Transcriptomics insights into the genetic regulation of root apical meristem exhaustion and determinate primary root growth in Pachycereus pringlei (Cactaceae)
Scientific Reports, 2018Co-Authors: Gustavo Rodriguez-alonso, Joseph G. Dubrovsky, Selene Napsucialy-mendivil, Marta Matvienko, Mayra L. López-valle, Pedro E. Lázaro-mixteco, Svetlana ShishkovaAbstract:Many Cactaceae species exhibit determinate growth of the primary root as a consequence of root apical meristem (RAM) exhaustion. The genetic regulation of this growth pattern is unknown. Here, we de novo assembled and annotated the root apex transcriptome of the Pachycereus pringlei primary root at three developmental stages, with active or exhausted RAM. The assembled transcriptome is robust and comprehensive, and was used to infer a transcriptional regulatory network of the primary root apex. Putative orthologues of Arabidopsis regulators of RAM maintenance, as well as putative lineage-specific transcripts were identified. The transcriptome revealed putative orthologues of most proteins involved in housekeeping processes, hormone signalling, and metabolic pathways. Our results suggest that specific transcriptional programs operate in the root apex at specific developmental time points. Moreover, the transcriptional state of the P . pringlei root apex as the RAM becomes exhausted is comparable to the transcriptional state of cells from the meristematic, elongation, and differentiation zones of Arabidopsis roots along the root axis. We suggest that the transcriptional program underlying the drought stress response is induced during Cactaceae root development, and that lineage-specific transcripts could contribute to RAM exhaustion in Cactaceae.
-
Determinate primary root growth as an adaptation to aridity in Cactaceae: towards an understanding of the evolution and genetic control of the trait
Annals of botany, 2013Co-Authors: Svetlana Shishkova, María Laura Las Peñas, Selene Napsucialy-mendivil, Marta Matvienko, Alexander Kozik, Jesús Montiel, Anallely Patiño, Joseph G. DubrovskyAbstract:†Background and Aims Species of Cactaceae are well adapted to arid habitats. Determinate growth of the primary root, which involves early and complete root apical meristem (RAM) exhaustion and differentiation of cells at the root tip, has been reported for some Cactoideae species as a root adaptation to aridity. In this study, the primary root growth patterns of Cactaceae taxa from diverse habitats are classified as being determinate or indeterminate, and the molecular mechanisms underlying RAM maintenance in Cactaceae are explored. Genes that were induced in the primary root of Stenocereus gummosus before RAM exhaustion are identified. †Methods Primary root growth was analysed in Cactaceae seedlings cultivated in vertically oriented Petri dishes. Differentially expressed transcripts were identified after reverse northern blots of clones from a suppression subtractive hybridization cDNA library. †KeyResults All species analysed from six tribes of the Cactoideae subfamily that inhabit arid and semi-arid regions exhibited determinate primary root growth. However, species from the Hylocereeae tribe, which inhabit mesic regions, exhibited mostly indeterminate primary root growth. Preliminary results suggest that seedlings of members of the Opuntioideae subfamily have mostly determinate primary root growth, whereas those of the Maihuenioideae and Pereskioideae subfamilies have mostly indeterminate primary root growth. Seven selected transcripts encoding homologues of heat stress transcription factor B4, histone deacetylase, fibrillarin, phosphoethanolamine methyltransferase, cytochrome P450 and gibberellin-regulated protein were upregulated inS.gummosus root tips during the initial growth phase. †Conclusions Primary root growth in Cactoideae species matches their environment. The data imply that determinate growth of the primary root became fixed after separation of the Cactiodeae/Opuntioideae and Maihuenioideae/ Pereskioideae lineages, and that the genetic regulation of RAM maintenance and its loss in Cactaceae is orchestrated by genes involved in the regulation of gene expression, signalling, and redox and hormonal responses.
Hugh D. Wilson - One of the best experts on this subject based on the ideXlab platform.
-
Opuntia engelmannii var. lindheimeri (Cultivated) 3
2011Co-Authors: Hugh D. WilsonAbstract:Opuntia engelmannii var. lindheimeri , Stems (as Opuntia lindheimeri). Family Cactaceae, Subclass Caryophyllidae. Origin: Cultivated.
-
Opuntia engelmannii var. lindheimeri (Cultivated)
2011Co-Authors: Hugh D. WilsonAbstract:Opuntia engelmannii var. lindheimeri , Fruiting stem (as Opuntia lindheimeri). Family Cactaceae, Subclass Caryophyllidae. Origin: Cultivated.
-
Opuntia engelmannii var. lindheimeri (Cultivated) 4
2011Co-Authors: Hugh D. WilsonAbstract:Opuntia engelmannii var. lindheimeri , Spineless aerole (as Opuntia lindheimeri ). Family Cactaceae, Subclass Caryophyllidae. Origin: Cultivated.
