Limits...
Expression pattern of four storage xyloglucan mobilization-related genes during seedling development of the rain forest tree Hymenaea courbaril L.

Brandão AD, Del Bem LE, Vincentz M, Buckeridge MS - J. Exp. Bot. (2009)

Bottom Line: The partial sequences were characterized by comparison with sequences available in the literature, and phylogenetic trees were assembled.HcXTH1 and HcBGAL1 were correlated to xyloglucan degradation and responded to auxin and light, being down-regulated when transport of auxin was prevented by N-1-naphthylphthalamic acid (NPA) and stimulated by constant light.It is concluded that gene expression plays a role in the control of the intercommunication system of the source-sink relationship during seeding growth, favouring its establishment in the shaded environment of the rain forest understorey.

View Article: PubMed Central - PubMed

Affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.

ABSTRACT
During seedling establishment, cotyledons of the rain forest tree Hymenaea courbaril mobilize storage cell wall xyloglucan to sustain growth. The polysaccharide is degraded and its products are transported to growing sink tissues. Auxin from the shoot controls the level of xyloglucan hydrolytic enzymes. It is not yet known how important the expression of these genes is for the control of storage xyloglucan degradation. In this work, partial cDNAs of the genes xyloglucan transglycosylase hydrolase (HcXTH1) and beta-galactosidase (HcBGAL1), both related to xyloglucan degradation, and two other genes related to sucrose metabolism [alkaline invertase (HcAlkIN1) and sucrose synthase (HcSUS1)], were isolated. The partial sequences were characterized by comparison with sequences available in the literature, and phylogenetic trees were assembled. Gene expression was evaluated at intervals of 6 h during 24 h in cotyledons, hypocotyl, roots, and leaves, using 45-d-old plantlets. HcXTH1 and HcBGAL1 were correlated to xyloglucan degradation and responded to auxin and light, being down-regulated when transport of auxin was prevented by N-1-naphthylphthalamic acid (NPA) and stimulated by constant light. Genes related to sucrose metabolism, HcAlkIN1 and HcSUS1, responded to inhibition of auxin transport in consonance with storage mobilization in the cotyledons. A model is proposed suggesting that auxin and light are involved in the control of the expression of genes related to storage xyloglucan mobilization in seedlings of H. courbaril. It is concluded that gene expression plays a role in the control of the intercommunication system of the source-sink relationship during seeding growth, favouring its establishment in the shaded environment of the rain forest understorey.

Show MeSH
Phylogenetic relationship of β-galactosidases of Angiosperms. Distances were calculated on the basis of positions 181–332 in A. thaliana (At-BGAL4). The nucleotide sequence can be accessed at NCBI: EU370969. Accession numbers are as follows: A. thaliana (At-GAL1, AT3G13750; At-GAL2, AT3G52840; At-GAL3, AT4G36360; At-BGAL4, AT5G56870; At-GAL5, AT1G45130; At-BGAL6, AT5G63800; At-GAL7, AT5G20710; At-BGAL8, AT2G28470; At-BGAL9, AT2G32810; At-BGAL10, AT5G63810; At-BGAL11, AT4G35010; At-GAL12, AT4G26140; At-BGAL13, AT2G16730; At-BGAL14, AT4G38590; At-GAL15, AT1G31740, At-BGAL16, AT1G77410; At-BGAL17, AT1G72990; Oryza sativa (10 members), Leguminosae (CanBGAL-4, CAA09457; CanBGAL-3, CAA06309; chickpea, AJ012687), tomato (AJ012796; AF020390; AJ012798), apple (L29451), and strawberry (AJ278705; AJ278703). The values presented represent the bootstraps.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC2657543&req=5

fig2: Phylogenetic relationship of β-galactosidases of Angiosperms. Distances were calculated on the basis of positions 181–332 in A. thaliana (At-BGAL4). The nucleotide sequence can be accessed at NCBI: EU370969. Accession numbers are as follows: A. thaliana (At-GAL1, AT3G13750; At-GAL2, AT3G52840; At-GAL3, AT4G36360; At-BGAL4, AT5G56870; At-GAL5, AT1G45130; At-BGAL6, AT5G63800; At-GAL7, AT5G20710; At-BGAL8, AT2G28470; At-BGAL9, AT2G32810; At-BGAL10, AT5G63810; At-BGAL11, AT4G35010; At-GAL12, AT4G26140; At-BGAL13, AT2G16730; At-BGAL14, AT4G38590; At-GAL15, AT1G31740, At-BGAL16, AT1G77410; At-BGAL17, AT1G72990; Oryza sativa (10 members), Leguminosae (CanBGAL-4, CAA09457; CanBGAL-3, CAA06309; chickpea, AJ012687), tomato (AJ012796; AF020390; AJ012798), apple (L29451), and strawberry (AJ278705; AJ278703). The values presented represent the bootstraps.

Mentions: The strategy to obtain partial cDNA sequences encoding H. courbaril relied basically on the use of two pairs of nested degenerated primers corresponding to conserved sequences. The amplification products with the expected length (Table S2) corresponding to 452 bp for actin, 435 bp for β-galactosidase, 333 bp for XTH, 819 bp for alkaline invertase, and 1146 bp for sucrose synthase were cloned and sequenced. Their identity was confirmed according to their similarity to known sequences. The H. courbaril (Hc) amino acid sequences were further characterized by a phylogenetic analysis. As expected, the partial sequences for HcBGAL1, HcXTH1, HcAlkIN1, and HcSUS1 were found to group more strongly with homologous sequences from Leguminosae. This analysis also allowed the more precise classification of the Hymenaea sequences. It was found that HcBGAL1 is more closely related to group I β-galactosidases; HcXTH1 to group I XTHs; HcAlkIN1 to group β alkaline invertase, and HcSUS1 to the SUS1 group of sucrose synthase (Supplementary Table S1 at JXB online). A comparison of HcBGAL1 with other plant β-galactosidases is shown in Fig. 2. This gene is inserted in a group that contains TBG4, an exogalactanase from tomato, and also genes from mung bean and chickpea. HcBGAL1 separated completely from a group that contains several genes from Arabidopsis and rice, except for the genes AtBGAL2, AtBGAL12, and AtBGAL4.


Expression pattern of four storage xyloglucan mobilization-related genes during seedling development of the rain forest tree Hymenaea courbaril L.

Brandão AD, Del Bem LE, Vincentz M, Buckeridge MS - J. Exp. Bot. (2009)

Phylogenetic relationship of β-galactosidases of Angiosperms. Distances were calculated on the basis of positions 181–332 in A. thaliana (At-BGAL4). The nucleotide sequence can be accessed at NCBI: EU370969. Accession numbers are as follows: A. thaliana (At-GAL1, AT3G13750; At-GAL2, AT3G52840; At-GAL3, AT4G36360; At-BGAL4, AT5G56870; At-GAL5, AT1G45130; At-BGAL6, AT5G63800; At-GAL7, AT5G20710; At-BGAL8, AT2G28470; At-BGAL9, AT2G32810; At-BGAL10, AT5G63810; At-BGAL11, AT4G35010; At-GAL12, AT4G26140; At-BGAL13, AT2G16730; At-BGAL14, AT4G38590; At-GAL15, AT1G31740, At-BGAL16, AT1G77410; At-BGAL17, AT1G72990; Oryza sativa (10 members), Leguminosae (CanBGAL-4, CAA09457; CanBGAL-3, CAA06309; chickpea, AJ012687), tomato (AJ012796; AF020390; AJ012798), apple (L29451), and strawberry (AJ278705; AJ278703). The values presented represent the bootstraps.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2657543&req=5

fig2: Phylogenetic relationship of β-galactosidases of Angiosperms. Distances were calculated on the basis of positions 181–332 in A. thaliana (At-BGAL4). The nucleotide sequence can be accessed at NCBI: EU370969. Accession numbers are as follows: A. thaliana (At-GAL1, AT3G13750; At-GAL2, AT3G52840; At-GAL3, AT4G36360; At-BGAL4, AT5G56870; At-GAL5, AT1G45130; At-BGAL6, AT5G63800; At-GAL7, AT5G20710; At-BGAL8, AT2G28470; At-BGAL9, AT2G32810; At-BGAL10, AT5G63810; At-BGAL11, AT4G35010; At-GAL12, AT4G26140; At-BGAL13, AT2G16730; At-BGAL14, AT4G38590; At-GAL15, AT1G31740, At-BGAL16, AT1G77410; At-BGAL17, AT1G72990; Oryza sativa (10 members), Leguminosae (CanBGAL-4, CAA09457; CanBGAL-3, CAA06309; chickpea, AJ012687), tomato (AJ012796; AF020390; AJ012798), apple (L29451), and strawberry (AJ278705; AJ278703). The values presented represent the bootstraps.
Mentions: The strategy to obtain partial cDNA sequences encoding H. courbaril relied basically on the use of two pairs of nested degenerated primers corresponding to conserved sequences. The amplification products with the expected length (Table S2) corresponding to 452 bp for actin, 435 bp for β-galactosidase, 333 bp for XTH, 819 bp for alkaline invertase, and 1146 bp for sucrose synthase were cloned and sequenced. Their identity was confirmed according to their similarity to known sequences. The H. courbaril (Hc) amino acid sequences were further characterized by a phylogenetic analysis. As expected, the partial sequences for HcBGAL1, HcXTH1, HcAlkIN1, and HcSUS1 were found to group more strongly with homologous sequences from Leguminosae. This analysis also allowed the more precise classification of the Hymenaea sequences. It was found that HcBGAL1 is more closely related to group I β-galactosidases; HcXTH1 to group I XTHs; HcAlkIN1 to group β alkaline invertase, and HcSUS1 to the SUS1 group of sucrose synthase (Supplementary Table S1 at JXB online). A comparison of HcBGAL1 with other plant β-galactosidases is shown in Fig. 2. This gene is inserted in a group that contains TBG4, an exogalactanase from tomato, and also genes from mung bean and chickpea. HcBGAL1 separated completely from a group that contains several genes from Arabidopsis and rice, except for the genes AtBGAL2, AtBGAL12, and AtBGAL4.

Bottom Line: The partial sequences were characterized by comparison with sequences available in the literature, and phylogenetic trees were assembled.HcXTH1 and HcBGAL1 were correlated to xyloglucan degradation and responded to auxin and light, being down-regulated when transport of auxin was prevented by N-1-naphthylphthalamic acid (NPA) and stimulated by constant light.It is concluded that gene expression plays a role in the control of the intercommunication system of the source-sink relationship during seeding growth, favouring its establishment in the shaded environment of the rain forest understorey.

View Article: PubMed Central - PubMed

Affiliation: Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas (UNICAMP), Campinas, SP, Brazil.

ABSTRACT
During seedling establishment, cotyledons of the rain forest tree Hymenaea courbaril mobilize storage cell wall xyloglucan to sustain growth. The polysaccharide is degraded and its products are transported to growing sink tissues. Auxin from the shoot controls the level of xyloglucan hydrolytic enzymes. It is not yet known how important the expression of these genes is for the control of storage xyloglucan degradation. In this work, partial cDNAs of the genes xyloglucan transglycosylase hydrolase (HcXTH1) and beta-galactosidase (HcBGAL1), both related to xyloglucan degradation, and two other genes related to sucrose metabolism [alkaline invertase (HcAlkIN1) and sucrose synthase (HcSUS1)], were isolated. The partial sequences were characterized by comparison with sequences available in the literature, and phylogenetic trees were assembled. Gene expression was evaluated at intervals of 6 h during 24 h in cotyledons, hypocotyl, roots, and leaves, using 45-d-old plantlets. HcXTH1 and HcBGAL1 were correlated to xyloglucan degradation and responded to auxin and light, being down-regulated when transport of auxin was prevented by N-1-naphthylphthalamic acid (NPA) and stimulated by constant light. Genes related to sucrose metabolism, HcAlkIN1 and HcSUS1, responded to inhibition of auxin transport in consonance with storage mobilization in the cotyledons. A model is proposed suggesting that auxin and light are involved in the control of the expression of genes related to storage xyloglucan mobilization in seedlings of H. courbaril. It is concluded that gene expression plays a role in the control of the intercommunication system of the source-sink relationship during seeding growth, favouring its establishment in the shaded environment of the rain forest understorey.

Show MeSH