Molecular and Biochemical Analysis of Periplastidial Starch Metabolism in the Cryptophyte Guillardia theta

ABSTRACT Starch in synchronously grown Guillardia theta cells accumulates throughout the light phase, followed by a linear degradation during the night. In contrast to the case for other unicellular algae such as Chlamydomonas reinhardtii, no starch turnover occurred in this organism under continuous light. The gene encoding granule-bound starch synthase (GBSS1), the enzyme responsible for amylose synthesis, displays a diurnal expression cycle. The pattern consisted of a maximal transcript abundance around the middle of the light phase and a very low level during the night. This diurnal regulation of GBSS1 transcript abundance was demonstrated to be independent of the circadian clock but tightly light regulated. A similar yet opposite type of regulation pattern was found for two α-amylase isoforms and for one of the two plastidic triose phosphate transporter genes investigated. In these cases, however, the transcript abundance peaked in the night phase. The second plastidic triose phosphate transporter gene had the GBSS1 mRNA abundance pattern. Quantification of the GBSS1 activity revealed that not only gene expression but also total enzyme activity exhibited a maximum in the middle of the light phase. To gain a first insight into the transport processes involved in starch biosynthesis in cryptophytes, we demonstrated the presence of both plastidic triose phosphate transporter and plastidic ATP/ADP transporter activities in proteoliposomes harboring either total membranes or plastid envelope membranes from G. theta. These molecular and biochemical data are discussed with respect to the environmental conditions experienced by G. theta and with respect to the unique subcellular location of starch in cryptophytes.

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Core temperature in the female rat: effect of pinealectomy or altered lighting

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.231.2.355 ◽

1976 ◽

Vol 231 (2) ◽

pp. 355-360 ◽

Cited By ~ 38

Author(s):

F Spencer ◽

HW Shirer ◽

JM Yochim

Keyword(s):

Core Temperature ◽

Continuous Light ◽

Mature Female ◽

Female Rats ◽

Female Rat ◽

Light Phase ◽

Continuous Darkness ◽

Temperature Rhythm ◽

Two Component ◽

Lighting Regimen

Radiotelemetry of core temperature in unrestrained, mature female rats revealed the existence of a 24-h rhythm that was bimodal. The principal peak occurred during the night under control conditions of 14 h light and 10 h darkness, and a less pronounced, secondary peak occurred 3-4 h after the onset of the light phase. Shifts in the phase of the photoperiod or alteration of the proportion of light per day revealed that the temperature rhythm was entrained by light, but that the two component peaks were governed by different aspects of the lighting regimen. Exposure of rats to continuous darkness, continuous light, or to a 20-h photoperiod revealed that the primary rhythm was endogenous, entrained by circadian photoperiods only, whereas the secondary rhythm was exogenous, requiring a circadian light/dark rhythm. A relationship between mean core temperature and ttion pressure, end-systolic L was constant, despite variations in filling and therefore independent of initial L and delta L; moreover, the L to which the ventricle shortened was determined by the course of the systolic force L-relation. Thus, irrespective of loading, delta L occurs within the confines of the contractile state-depdendent isovolumic force-L relation and where the latter is equivalent to the end-systolic force-length relation.

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Transcriptional profiles of organellar metabolite transporters during induction of crassulacean acid metabolism in Mesembryanthemum crystallinum

Functional Plant Biology ◽

10.1071/fp04188 ◽

2005 ◽

Vol 32 (5) ◽

pp. 451 ◽

Cited By ~ 21

Author(s):

Shin Kore-eda ◽

Chiyuki Noake ◽

Masahisa Ohishi ◽

Jun-ichi Ohnishi ◽

John C. Cushman

Keyword(s):

Crassulacean Acid Metabolism ◽

Acid Metabolism ◽

Expression Patterns ◽

Transcript Abundance ◽

Transport Processes ◽

Mesembryanthemum Crystallinum ◽

Water Deficit Stress ◽

Diurnal Changes ◽

Metabolite Transport ◽

Leaf Tissues

Metabolite transport across multiple organellar compartments is essential for the operation of crassulacean acid metabolism (CAM). To investigate potential circadian regulation of inter-organellar metabolite transport processes, we have identified eight full-length cDNAs encoding an organellar triose phosphate / Pi translocator (McTPT1), a phosphoenolpyruvate / Pi translocator (McPPT1), two glucose-6-phosphate / Pi translocators (McGPT1, 2), two plastidic Pi translocator-like proteins (McPTL1, 2), two adenylate transporters (McANT1, 2), a dicarboxylate transporter (McDCT2), and a partial cDNA encoding a second dicarboxylate transporter (McDCT1) in the model CAM plant, Mesembryanthemum crystallinum L. We next investigated day / night changes in steady-state transcript abundance of each of these transporters in plants performing either C3 photosynthesis or CAM induced by salinity or water-deficit stress. We observed that the expression of both isogenes of the glucose-6-phosphate / Pi translocator (McGPT1, 2) was enhanced by CAM induction, with McGPT2 transcripts exhibiting much more pronounced diurnal changes in transcript abundance than McGPT1. Transcripts for McTPT1, McPPT1, and McDCT1 also exhibited more pronounced diurnal changes in abundance in the CAM mode relative to the C3 mode. McGPT2 and McDCT1 transcripts exhibited sustained oscillations for at least 3 d under constant light and temperature conditions suggesting their expression is under circadian clock control. McTPT1 and McGPT2 transcripts were preferentially expressed in leaf tissues in either C3 or CAM modes. The leaf-specific and / or circadian controlled gene expression patterns are consistent with McTPT1, McGPT2 and McDCT1 playing CAM-specific metabolite transport roles.

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Nematode-Induced Changes of Transporter Gene Expression in Arabidopsis Roots

Molecular Plant-Microbe Interactions ◽

10.1094/mpmi-18-1247 ◽

2005 ◽

Vol 18 (12) ◽

pp. 1247-1257 ◽

Cited By ~ 89

Author(s):

Ulrich Z. Hammes ◽

Daniel P. Schachtman ◽

R. Howard Berg ◽

Erik Nielsen ◽

Wolfgang Koch ◽

...

Keyword(s):

Gene Families ◽

Transcript Abundance ◽

Giant Cells ◽

Transport Processes ◽

Transfer Cells ◽

Parasitic Nematodes ◽

Feeding Site ◽

Feeding Sites ◽

The Many ◽

And Function

Root-knot plant-parasitic nematodes (Meloidogyne spp.) account for much of the damage inflicted to plants by nematodes. The feeding sites of these nematodes consist of “giant” cells, which have characteristics of transfer cells found in other parts of plants. Increased transport activity across the plasma membrane is a hallmark of transfer cells, and giant cells provide nutrition for nematodes; therefore, we initiated a study to identify the transport processes that contribute to the development and function of nematode-induced feeding sites. The study was conducted over a 4-week period, during which time the large changes in the development of giant cells were documented. The Arabidopsis ATH1 GeneChip was used to identify the many transporter genes that were regulated by nematode infestation. Expression of 50 transporter genes from 18 different gene families was significantly changed upon nematode infestation. Sixteen transporter genes were studied in more detail using real-time reverse-transcriptase polymerase chain reaction to determine transcript abundance in nematode-induced galls that contain giant cells and uninfested regions of the root. Certain genes were expressed primarily in galls whereas others were expressed primarily in the uninfested regions of the root, and a third group was expressed evenly throughout the root. Multiple transport processes are regulated and these may play important roles in nematode feeding-site establishment and maintenance.

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Transcriptomic and proteomic analysis of putative digestive proteases in the salivary gland and gut of Empoasca (Matsumurasca) onukii Matsuda

10.21203/rs.3.rs-25607/v2 ◽

2020 ◽

Author(s):

Ensi Shao ◽

Yujuan Song ◽

Yaomin Wang ◽

Yichen Liao ◽

Yufei Luo ◽

...

Keyword(s):

Salivary Gland ◽

Enzymatic Activity ◽

Serine Proteases ◽

Cathepsin L ◽

Transcript Abundance ◽

Nilaparvata Lugens ◽

Integrated Analysis ◽

Abundance Pattern ◽

Digestive Proteases ◽

Tea Plants

Abstract Background: Infestation by tea green leafhoppers, Empoasca (Matsumurasca) onukii , could cause a series of biochemical changes in tea leaves. As a typical cell-rupture feeder, E. onukii secretes proteases while probing with its stylet into the tender shoots of tea plants ( Camellia sinensis ). This study identified and analyzed proteases specifically expressed in the salivary gland (SG) and gut of E. onukii through enzymatic activity assays, complemented with an integrated analysis of transcriptome and proteome data.Results: In total, 129 contigs representing seven types of putative proteases were identified. Transcript abundance of digestive proteases and enzymatic activity assays showed that cathepsin B-like protease, cathepsin L-like protease, and serine proteases (trypsin- and chymotrypsin-like protease) were highly abundant in the gut while moderately abundant in the SG. The abundance pattern of digestive proteases in the SG and gut of E. onukii differed from that of other hemipterans including Nilaparvata lugens , Laodelphax striatellus , Acyrthosiphum pisum , Halyomorpha halys and Nephotettix cincticeps . Phylogenetic analysis showed that aminopeptidase N-like proteins and serine proteases abundant in the SG or gut of hemipterans were distributed to two distinct clusters.Conclusions: Altogether, this study provide insightful information on the digestive system of E. onukii and observed different patterns of proteases abundant in the SG and gut of E. onukii , in comparison with other five hemipteran species. These results will be beneficial in understanding the interaction between tea plants and E. onukii .

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Transcriptomic and proteomic analysis of putative digestive proteases in the salivary gland and gut of Empoasca(Matsumurasca) onukii Matsuda

10.21203/rs.3.rs-25607/v1 ◽

2020 ◽

Author(s):

Ensi Shao ◽

Yujuan Song ◽

Yaomin Wang ◽

Yichen Liao ◽

Yufei Luo ◽

...

Keyword(s):

Salivary Gland ◽

Enzymatic Activity ◽

Serine Proteases ◽

Cathepsin L ◽

Transcript Abundance ◽

Nilaparvata Lugens ◽

Integrated Analysis ◽

Abundance Pattern ◽

Digestive Proteases ◽

Tea Plants

Abstract Background: Infestation by tea green leafhoppers, Empoasca (Matsumurasca) onukii, could cause a series of biochemical changes in tea leaves. As a typical cell-rupture feeder, E. onukii secretes proteases while probing with its stylet into the tender shoots of tea plants (Camellia sinensis). This study identified and analyzed proteases specifically expressed in the salivary gland (SG) and gut of E. onukii through enzymatic activity assays, complemented with an integrated analysis of transcriptome and proteome data.Results: In total, 129 contigs representing seven types of putative proteases were identified. Transcript abundance of digestive proteases and enzymatic activity assays showed that cathepsin B, cathepsin L, and serine proteases (trypsin and chymotrypsin) were highly abundant in the gut while moderately abundant in the SG. The abundance pattern of digestive proteases in the SG and gut of E. onukii differed from that of other hemipterans including Nilaparvata lugens, Laodelphax striatellus, Nephotettix cincticeps and Acyrthosiphum pisum. Phylogenetic analysis showed that aminopeptidase N-like proteins and serine proteases abundant in the SG or gut of hemipterans were distributed to two distinct clusters. Conclusions: Altogether, this study provide insightful information on the digestive system of E. onukii and observed different patterns of proteases abundant in the SG and gut of E. onukii, in comparison with other five hemipteran species. These results will be beneficial in understanding the interaction between tea plants and E. onukii.

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Changes in CsFT Transcript Abundance at the Onset of Low-temperature Floral Induction in Sweet Orange

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.138.3.184 ◽

2013 ◽

Vol 138 (3) ◽

pp. 184-189 ◽

Cited By ~ 7

Author(s):

Eduardo J. Chica ◽

L. Gene Albrigo

Keyword(s):

Sweet Orange ◽

Floral Induction ◽

Continuous Light ◽

Transcript Abundance ◽

Flowering Locus T ◽

Transcript Accumulation ◽

Initial Exposure ◽

Induction Process ◽

Gene Transcripts

As in arabidopsis (Arabidopsis thaliana), putative citrus (Citrus) Flowering locus T (FT) homologs are strong promoters of flowering and apparently are key components of the molecular mechanism controlling floral induction in these species. An abundance of citrus FT gene transcripts during floral induction is consistent with the role of their products as floral-promoting signals. However, specific details about how the floral induction process is initiated and sustained remain largely unknown. We report changes in transcript abundance of a FT gene (CsFT) from sweet orange (Citrus sinensis) at the onset of floral induction by low temperatures and at different times of the day. Using a combination of field and growth room experiments, we determined that the abundance of CsFT transcripts increased within 1 day after initial exposure to cool floral-inductive temperatures, and that CsFT transcript abundance was higher in the afternoon than in the morning and evening. The presence of photoperiod cycles seemed to be required to sustain the increasing CsFT transcript abundance, because exposure to floral inductive conditions under continuous light or darkness did not increase the abundance of CsFT transcripts after 3 days. Our results suggest that the regulation of CsFT expression responds rapidly (overnight) to the onset of floral-inductive cool temperatures, is sensitive to changes in temperature, and requires alternation of light and dark cycles to sustain transcript accumulation during induction.

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Differential Expression of var Gene Groups Is Associated with Morbidity Caused by Plasmodium falciparum Infection in Tanzanian Children

Infection and Immunity ◽

10.1128/iai.02073-05 ◽

2006 ◽

Vol 74 (7) ◽

pp. 3904-3911 ◽

Cited By ~ 135

Author(s):

Matthias Rottmann ◽

Thomas Lavstsen ◽

Joseph Paschal Mugasa ◽

Mirjam Kaestli ◽

Anja T. R. Jensen ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Transcript Abundance ◽

Clinical Malaria ◽

Asymptomatic Malaria ◽

Abundance Pattern ◽

Real Time Quantitative Pcr ◽

Clinical Presentations ◽

Group A ◽

Asymptomatic Infections ◽

Sequence Similarities

ABSTRACT The var gene family of Plasmodium falciparum encodes the variant surface antigen Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1). PfEMP1 is considered an important pathogenicity factor in P. falciparum infection because it mediates cytoadherence to host cell endothelial receptors. var genes can be grouped into three major groups, A, B, and C, and the conserved var genes, var1-4, according to sequence similarities in coding and noncoding upstream regions. Using real-time quantitative PCR in a study conducted in Tanzania, the var transcript abundances of the different var gene groups were compared among patients with severe, uncomplicated, and asymptomatic malaria. Transcripts of var group A and B genes were more abundant in patients with severe malaria than in patients with uncomplicated malaria. In general, the transcript abundances of var group A and B genes were higher for children with clinical malaria than for children with asymptomatic infections. The var group C and var1-like transcript abundances were similar between the three sample groups. A transcript abundance pattern similar to that for var group A was observed for var2csa and var3-like genes. These results suggest that substantial and systematic differences in var gene expression exist between different clinical presentations.

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Transcriptomic and proteomic analysis of putative digestive proteases in the salivary gland and gut of Empoasca (Matsumurasca) onukii Matsuda

BMC Genomics ◽

10.1186/s12864-021-07578-2 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Ensi Shao ◽

Yujuan Song ◽

Yaomin Wang ◽

Yichen Liao ◽

Yufei Luo ◽

...

Keyword(s):

Salivary Gland ◽

Enzymatic Activity ◽

Serine Proteases ◽

Cathepsin L ◽

Transcript Abundance ◽

Nilaparvata Lugens ◽

Integrated Analysis ◽

Abundance Pattern ◽

Digestive Proteases ◽

Tea Plants

Abstract Background Infestation by tea green leafhoppers (Empoasca (Matsumurasca) onukii) can cause a series of biochemical changes in tea leaves. As a typical cell-rupture feeder, E. onukii secretes proteases while using its stylet to probe the tender shoots of tea plants (Camellia sinensis). This study identified and analyzed proteases expressed specifically in the salivary gland (SG) and gut of E. onukii through enzymatic activity assays complemented with an integrated analysis of transcriptomic and proteomic data. Results In total, 129 contigs representing seven types of putative proteases were identified. Transcript abundance of digestive proteases and enzymatic activity assays showed that cathepsin B-like protease, cathepsin L-like protease, and serine proteases (trypsin- and chymotrypsin-like protease) were highly abundant in the gut but moderately abundant in the SG. The abundance pattern of digestive proteases in the SG and gut of E. onukii differed from that of other hemipterans, including Nilaparvata lugens, Laodelphax striatellus, Acyrthosiphum pisum, Halyomorpha halys and Nephotettix cincticeps. Phylogenetic analysis showed that aminopeptidase N-like proteins and serine proteases abundant in the SG or gut of hemipterans formed two distinct clusters. Conclusions Altogether, this study provides insightful information on the digestive system of E. onukii. Compared to five other hemipteran species, we observed different patterns of proteases abundant in the SG and gut of E. onukii. These results will be beneficial in understanding the interaction between tea plants and E. onukii.

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Trimeric G proteins modulate the dynamic interaction of PKAII with the Golgi complex

Journal of Cell Science ◽

10.1242/jcs.112.22.3869 ◽

1999 ◽

Vol 112 (22) ◽

pp. 3869-3878 ◽

Cited By ~ 1

Author(s):

M.E. Martin ◽

J. Hidalgo ◽

F.M. Vega ◽

A. Velasco

Keyword(s):

G Proteins ◽

Golgi Complex ◽

Mammalian Cells ◽

Protein Transport ◽

Brefeldin A ◽

Subcellular Location ◽

Transport Processes ◽

Golgi Stack ◽

Golgi Membranes

The Golgi complex represents a major subcellular location of protein kinase A (PKA) concentration in mammalian cells where it has been previously shown to be involved in vesicle-mediated protein transport processes. We have studied the factors that influence the interaction of PKA typeII subunits with the Golgi complex. In addition to the cytosol, both the catalytic (Calpha) and regulatory (RIIalpha) subunits of PKAII were detected at both sides of the Golgi stack, particularly in elements of the cis- and trans-Golgi networks. PKAII subunits, in contrast, were practically absent from the middle Golgi cisternae. Cell treatment with either brefeldin A, AlF(4-) or at low temperature induced PKAII dissociation from the Golgi complex and redistribution to the cytosol. This suggested the existence of a cycle of association/dissociation of PKAII holoenzyme to the Golgi. The interaction of purified RIIalpha with Golgi membranes was studied in vitro and found not to be affected by brefeldin A while it was sensitive to modulators of heterotrimeric G proteins such as AlF(4-), GTPgammaS, beta(gamma) subunits and mastoparan. RII(alphaa) binding was stimulated by recombinant, myristoylated Galpha(i3) subunit and inhibited by cAMP. Pretreatment of Golgi membranes with bacterial toxins known to catalyze ADP-ribosylation of selected Galpha subunits also modified RIIalpha binding. Taken together the data support a regulatory role for Golgi-associated Galpha proteins in PKAII recruitment from the cytosol.

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