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PubMed2026

Host genetic regulation of xylem-resident Pseudomonas enhances cucumber growth.

BACKGROUND: Although endophytic microorganisms play a critical role in plant growth and stress resilience, the genetic basis underlying host selection of beneficial microbiota-particularly within the xylem-remains poorly understood. Cucumber (Cucumis sativus), as a crop model with a well-developed system for studying vascular biology, offers a valuable system to investigate the host genetic determinants of xylem microbiome assembly. RESULTS: By conducting population-level microbiome profiling across 109 cucumber accessions, we identified a conserved xylem microbiota dominated by Proteobacteria. Within this community, 20 core amplicon sequence variants (ASVs) were consistently present in xylem sap. Genome-wide association mapping identified a host genetic locus, CsXPR1, which encodes a tetratricopeptide repeat protein that regulates the abundance of the dominant xylem-colonized Pseudomonas ASV_4. Colonization patterns of ASV_4 varied across host genotypes and were correlated with CsXPR1 expression levels, suggesting a precision genetic regulation of bacterial entry into vascular tissues. Pseudomonas fulva strain 220, with 97% 16S rRNA gene identity with ASV_4, could colonize in cucumber xylem by inoculation of either roots or leaves. Genome analysis and plate assays revealed the biosynthesis of indole-3-acetic acid (IAA), solubilization of phosphate, and a range of plant beneficial traits in strain 220. Inoculation with strain 220 significantly enhanced growth in cucumber, but only in CsXPR1 haplotype that exhibited high gene expression and higher recruitment capacity of the strain. These benefits included notable increases in plant height (38%), stem diameter (36%), leaf area (61%), fresh and dry weight (51% and 85%, respectively), and a 4.57-fold increase in 4-methyleneglutamine content within the xylem sap. CONCLUSION: Our findings reveal a complete "gene-to-function" pathway where the host gene CsXPR1 mediates a genotype-dependent growth promotion. It achieves this by regulating the xylem colonization of a beneficial bacterium, Pseudomonas fulva, which in turn enhances plant growth by enriching the xylem sap with the key metabolite 4-methyleneglutamine. Video Abstract.

Cucumis sativus↗
PubMed1989

MAP 1A and MAP 1B are structurally related microtubule associated proteins with distinct developmental patterns in the CNS.

Five high-molecular-weight microtubule-associated proteins (MAPs) were identified in brain tissue in previous work from this laboratory (Bloom et al., 1984). These proteins were termed MAP 1A, 1B, 1C, 2A, and 2B. The MAP 1's differed from the MAP 2's, and showed little evidence of interrelationship on the basis of immunological and biochemical comparison. We report here that MAP 1A and MAP 1B are, in fact, related at the level of subunit composition. Immunoprecipitation of the individual MAPs showed that both contained low-molecular-weight subunits of Mr 30,000 and Mr 19,000 (light chains 1 and 3). An additional subunit, light chain 2 (Mr 28,000), was primarily found in preparations of MAP 1A. The light chains co-sedimented with microtubules after chymotryptic digestion of the MAPs. This suggested an association of the light chains with the microtubule binding domains of the MAPs, which are identified here as distinct fragments of Mr 60,000 for MAP 1A and 120,000 for MAP 1B. A panel of monoclonal anti-MAP 1A and anti-MAP 1B antibodies, including one that reacts with a common phosphorylated epitope, was used to examine the distribution of these proteins in the developing rat brain and spinal cord. MAP 1B was found to be abundant in the newborn brain and to decrease with development, in contrast to MAP 1A which increased with development. By immunohistochemistry MAP 1B was found to be highly concentrated in developing axonal processes in the cerebellar molecular layer, the corticospinal tract, the mossy fibers in the hippocampus, and the olfactory nerve. Of particular interest, the mossy fiber and olfactory nerve staining persisted in the adult, indicating continued outgrowth of the mossy fibers as well as olfactory nerve axons. MAP 1A staining was, in contrast, weak or absent in developing axonal fibers but moderate in mature axons and intense in developing and mature dendritic processes. Our results indicate that MAP 1A and MAP 1B are structurally related components of the neuronal cytoskeleton with complementary patterns of expression.

Animals↗
PubMed1995

Overexpression of an epitope-tagged beta-tubulin in Chinese hamster ovary cells causes an increase in endogenous alpha-tubulin synthesis.

A Chinese hamster beta-tubulin cDNA, engineered to express a 9 amino acid epitope from the influenza hemagglutinin antigen (HA), was transfected into Chinese hamster ovary (CHO) cells. The recombinant protein (HA beta 1-tubulin) appeared to behave normally by the following criteria: immunofluorescence indicated that HA beta 1-tubulin incorporated into all classes of interphase and spindle microtubules as well as microtubule organizing centers. The sensitivity of the cells expressing HA beta 1-tubulin to Colcemid and taxol was unchanged. A 210 kD microtubule associated protein (MAP) remained associated with microtubules that incorporate HA beta 1-tubulin. The synthesis of both endogenous beta-tubulin and HA beta 1-tubulin was repressed by colchicine. The HA beta 1-tubulin incorporated into microtubules to the same extent as the endogenous beta-tubulin, and the overall extent of microtubule assembly in transfected cells was unchanged. Finally, transfected cells had normal growth rates and morphologies. When effects on endogenous tubulin production were measured, it was found that expression of the HA beta 1-tubulin reduced the synthesis of endogenous wild-type beta-tubulin but increased the synthesis of alpha-tubulin. At steady state, a small increase in total tubulin consistent with the increased synthesis of alpha-tubulin was found. The results indicate that expression of excess exogenous beta-tubulin perturbs the synthesis of endogenous alpha-tubulin in a manner that is not easily explained by current models of tubulin regulation. The changes in tubulin synthesis along with degradation of excess tubulin subunits may reflect mechanisms that exist to ensure coordinate levels of alpha- and beta-tubulin for assembly.

Amino Acid Sequence↗
PubMed2002

Long wavelength fluorophores and cell-by-cell correction for autofluorescence significantly improves the accuracy of flow cytometric energy transfer measurements on a dual-laser benchtop flow cytometer.

BACKGROUND: Flow cytometric fluorescence resonance energy transfer (FCET) is an efficient method to map associations between biomolecules because of its high sensitivity to changes in molecular distances in the range of 1-10 nm. However, the requirement for a dual-laser instrument and the need for a relatively high signal-to-noise system (i.e., high expression level of the molecules) pose limitations to a wide application of the method. METHODS: Antibodies conjugated to cyanines 3 and 5 (Cy3 and Cy5) were used to label membrane proteins on the cell surface. FCET measurements were made on a widely used benchtop dual-laser flow cytometer, the FACSCalibur, by using cell-by-cell analysis of energy transfer efficiency.ResultsTo increase the accuracy of FCET measurements, we applied a long wavelength donor-acceptor pair, Cy3 and Cy5, which beneficially affected the signal-to-noise ratio in comparison with the classic pair of fluorescein and rhodamine. A new algorithm for cell-by-cell correction of autofluorescence further improved the sensitivity of the technique; cell subpopulations with only slightly different FCET efficiencies could be identified. The new FCET technique was tested on various direct and indirect immunofluorescent labeling strategies. The highest FCET values could be measured when applying direct labeling on both (donor and acceptor) sides. Upon increasing the complexity of the labeling scheme by introducing secondary antibodies, we detected a decrease in the energy transfer efficiency. CONCLUSIONS: We developed a new FCET protocol by applying long wavelength excitation and detection of fluorescence and by refining autofluorescence correction. The increased accuracy of the new method makes cells with low receptor expression amenable to FCET investigation, and the new approach can be implemented easily on a commercially available dual-laser flow cytometer, such as a FACSCalibur.

Algorithms↗
PubMed1989

Genetic analysis of new restriction fragment length polymorphisms (RFLP) in the human IgH constant gene locus.

The human immunoglobulin heavy chain constant gene locus (IGHC) is polymorphic at both the protein (Gm and A2m allotypes) and the DNA level [RFLP for the gamma genes (IGHG), the switch mu region (IGHSM) and the switch alpha regions (IGHSA)]. The polymorphisms have been a valuable tool for assessment of the IGHC locus organization and a variety of population genetics and immunological investigations. In this study three new probes, identifying regions related to the IGHG (IGHPG and IGHSG) or IGHA (IGHAT) genes, have been employed to describe 11 different loci, 6 of which were polymorphic. Most of the polymorphisms are probably due to short insertions/deletions, particularly the SG regions, due to their repetitive structure. Ten loci were assigned to the IGHC region on the basis of known restriction maps, deletion mapping and association with mapped RFLP; the 11th, despite a striking sequence similarity with the IGHPG regions, could not be assigned to any known IGHC subregion. Analysis of these and previously known IGHG RFLP in a sample of 65 unrelated subjects plus 15 families allowed us to draw a genetic map, with particularly high resolution in the GP-G2-G4 genes region, revealing a marked discontinuity in the linkage disequilibrium values between pairs of adjacent loci.

Biological Evolution↗
PubMed1995

Effects of eye position on auditory localization and neural representation of space in superior colliculus of cats.

The maps of visual and auditory space within the superior colliculus are in approximate register both with each other and with the underlying motor maps associated with orienting responses. The fact that eyes and ears can move independently poses a problem for the sensorimotor organization of these two modalities. By monitoring eye and pinna positions in alert, head-fixed cats, we showed that the accuracy of saccadic eye movements to auditory targets was little affected by eye eccentricity (range +/- 15 deg) at the onset of the sound. A possible neural basis for this behavioral compensation was suggested by recordings from superior colliculus neurons. The preferred sound directions of some neurons in the deep layers of this midbrain nucleus exhibited a shift with the direction of gaze, while in others the response throughout the auditory receptive field was either increased or decreased, suggesting that changes in eye position alter the gain of the auditory response.

Acoustic Stimulation↗
PubMed2004

The development of lettuce backcross inbred lines (BILs) for exploitation of the Lactuca saligna (wild lettuce) germplasm.

Backcross inbred lines (BILs) were developed in which chromosome segments of Lactuca saligna (wild lettuce) were introgressed into L. sativa (lettuce). These lines were developed by four to five backcrosses and one generation of selfing. The first three generations of backcrossing were random. Marker-assisted selection began in the BC(4) generation and continued until the final set of BILs was reached. A set of 28 lines was selected that together contained 96% of the L. saligna genome. Of these lines, 20 had a single homozygous introgression (BILs), four had two homozygous introgressions (doubleBILs) and four lines had a heterozygous single introgression (preBILs). Segregation ratios in backcross generations were compared to distorted segregation ratios in an F(2) population, and the results indicated that most of the distorted segregations can be explained by genetic effects on pollen- or egg-cell fitness. By means of BIL association mapping we were able to map 12 morphological traits and hundreds of additional amplified fragment length polymorphic (AFLP) markers. The total AFLP map now comprises 757 markers. This set of BILs is very useful for future genetic studies.

Chromosome Mapping↗
PubMed2005

Genetic structure and diversity of European flint maize populations determined with SSR analyses of individuals and bulks.

Landraces of maize represent a valuable genetic resource for breeding and genetic studies. Using simple sequence repeat (SSR) markers, we analysed five flint maize populations from Central Europe that had played an important role in the pre-hybrid era in Germany. Our objectives were to (1) investigate the molecular genetic diversity within and among the populations based on the SSR analysis of individuals, (2) compare these results of the SSR analysis based on individuals with those based on bulks, (3) examine genotype frequencies for deviations from Hardy-Weinberg equilibrium (HWE) at individual loci, and (4) test for linkage disequilibrium (LD) between pairs of loci within populations. Thirty individuals and their bulked DNA per population were fingerprinted with 55 SSR markers. Across all populations, 46.7% of the SSR markers deviated significantly from HWE, with an excess of homozygosity in 97% of the cases. This excess of homozygosity can largely be explained by experimental errors during the amplification of SSRs apart from genuine genetic causes. Allele frequencies of the SSR analyses of individuals and bulks were significantly correlated (r=0.85, P< 0.01), suggesting that SSR analysis of bulks is very cost-effective for large-scale molecular characterisation of germ plasm collections. No evidence for genome-wide LD among pairs of loci was observed, indicating that the populations are well suited for high resolution association mapping studies.

Europe↗
PubMed2006

Linkage disequilibrium in cultivated grapevine, Vitis vinifera L.

We present here the first study of linkage disequilibrium (LD) in cultivated grapevine, Vitis vinifera L. subsp. vinifera (sativa), an outcrossing highly heterozygous perennial species. Our goal was to characterize the amount and pattern of LD at the scale of a few centiMorgans (cM) between 38 microsatellite loci located on five linkage groups, in order to assess its origin and potential applications. We used a core collection of 141 cultivars representing the diversity of the cultivated compartment. LD was evaluated with both independence tests and multilocus r2, both on raw genotypic and reconstructed haplotypic data. Significant genotypic LD was found only within linkage groups, extending up to 16.8 cM. It appeared not to be influenced by the weak structure of the sample and seemed to be mainly of haplotypic origin. Significant haplotypic LD was found over 30 cM. Both genotypic and haplotypic r2 values declined to around 0.1 within 5-10 cM, suggesting a rather narrow genetic base of the cultivated compartment and limited recombination since domestication events. These first results open up a few application opportunities for association mapping of QTLs and marker assisted selection.

Chromosome Mapping↗
PubMed2006

Genetic diversity analysis of traditional and improved Indonesian rice (Oryza sativa L.) germplasm using microsatellite markers.

The archipelago of Indonesia has a long history of rice production across a broad range of rice-growing environments resulting in a diverse array of local Indonesian rice varieties. Although some have been incorporated into modern breeding programs, the vast majority of these landraces remain untapped. To better understand this rich source of genetic diversity we have characterized 330 rice accessions, including 246 Indonesian landraces and 63 Indonesian improved cultivars, using 30 fluorescently-labeled microsatellite markers. The landraces were selected across 21 provinces and include representatives of the classical subpopulations of cere, bulu, and gundil rices. A total of 394 alleles were detected at the 30 simple sequence repeat loci, with an average number of 13 alleles per locus across all accessions, and an average polymorphism information content value of 0.66. Genetic diversity analysis characterized the Indonesian landraces as 68% indica and 32% tropical japonica, with an indica gene diversity of 0.53 and a tropical japonica gene diversity of 0.56, and a Fst of 0.38 between the two groups. All of the improved varieties sampled were indica, and had an average gene diversity of 0.46. A set of high quality Indonesian varieties, including Rojolele, formed a separate cluster within the tropical japonicas. This germplasm presents a valuable source of diversity for future breeding and association mapping efforts.

Chromosomes, Plant↗
PubMed2002

Identification of novel candidate genes in the diffuse panbronchiolitis critical region of the class I human MHC.

Diffuse panbronchiolitis (DPB) is an unusual form of bronchiolar disease affecting exclusively East Asians. Strong associations of DPB with the class I human leukocyte antigens HLA-B54 in Japan and China and HLA-A11 in Korea suggest that the susceptible locus for DPB is located between the HLA-B and HLA-A genes. We have previously reported that the susceptibility gene for DPB could be localized within a 200-kb segment between the S and TFIIH loci in the HLA class I region, using refined microsatellite-based association mapping. However, no genes have been recognized in this candidate region to date. In order to identify a novel candidate gene for DPB from this segment, the expressed sequence tag databases were searched using the genomic sequence. As a result, a cDNA clone was isolated from a human lung cDNA library. This gene, designated C6orf37 (Chromosome 6 open reading frame 37), spans approximately 2.5 kb and consists of two exons encoding a 235-amino acid protein, sharing homology with the mucin-like domain of human zonadhesin, which is a sperm multiple-domain transmembrane protein with the sperm zona pellucida binding activity. Unexpectedly, RT-PCR analysis detected transcripts from the anti-sense DNA strand of this C6orf37 locus. The gene designated as C6orf37OS (C6orf37 Opposite Strand) and represented by these anti-sense transcripts contained no open reading frame. The transcripts from C6orf37 and C6orf37OS were observed in numerous tissues, with most-abundant expression in lung, kidney, and testis. Taken together, these results, especially the abundant expression in lung, indicate that C6orf37 and C6orf37OS are excellent candidate genes for DPB.

Amino Acid Sequence↗
PubMed2002

A genome screen for linkage disequilibrium in HLA-DRB1*15-positive Germans with multiple sclerosis based on 4666 microsatellite markers.

Multiple sclerosis (MS) is a demyelinating disorder of the central nervous system with putative autoimmune aetiology and complex genetic background. Here, we report the results of a genome screen for linkage disequilibrium (LD) by using 6000 microsatellite markers in 198 HLA-DRB1*15-positive MS patients and 198 unrelated controls (pooled DNA); 4666 analysed markers could be included in the resulting association map, from which 87 revealed significant differences between MS cases and controls.

Adult↗
PubMed2026

Genetic evidence links hypertension to accelerated brain aging.

Hypertension affects one-third of adults and is a major comorbidity of neurocognitive disorders. The causal relationship, shared genetic architecture, and upstream mechanisms linking hypertension to brain aging remain unclear. Hypertension GWAS datasets from MVP and FinnGen R12 were meta-analyzed as the exposure, and a European-ancestry brain age gap (BAG) GWAS derived from the UK Biobank and LIFE-Adult cohorts was used as the outcome. MR and GSMR assessed causality. LDSC, HDL, and S-LDSC estimated genetic correlation. Four TWAS methods (MAGMA, FUSION, JTI-PrediXcan, FOCUS) mapped associations to genes, followed by SMR for causal validation and PoPS for prioritization. GSMAP with spatial transcriptomics characterized regional and cell-type enrichment. Hypertension and brain aging were genetically correlated, and MR and GSMR analyses suggested a causal effect of hypertension on increased brain age gap. TWAS identified 15 shared Hypertension-BAG genes, 10 supported by SMR. PoPS prioritized TRIM47 as the core gene. Shared signals were enriched in meninges, fiber tracts, cortical layer 1, and CA1 stratum lacunosum/radiatum, with cell-type enrichment in meninges, smooth muscle cells, oligodendrocytes, and astrocyte subtypes. Hypertension is genetically correlated with, and shows evidence of a causal effect on, accelerated brain aging. TRIM47 is a core gene bridging hypertension and BAG. GSMAP-based spatial enrichment provides a hypothesis-generating framework for understanding vascular, meningeal, and myelin-related pathways linking hypertension to increased brain age gap.

Humans↗
PubMed1986

Fluorescence probing of the function-specific cysteines of rat microsomal NADPH-cytochrome P-450 reductase.

Titration of NADPH-cytochrome P-450 reductase with a fluorigenic maleimide suggests that approximately four cysteines are initially accessible and in close proximity to four tryptophans. Perturbation of the cysteines and/or tryptophans results in concomitant decreases in enzymic activity. These cysteines were correlated with functional components by binding studies and subsequent tryptic peptide mapping on the acid mobile phase-reverse phase HPLC. Adenine nucleotides and cytochrome c block labelling of the more hydrophilic peptides, while detergents facilitate labelling of the more hydrophobic peptides. The more hydrophobic peptides contain the microsomal binding site of cytochrome P-450. Removal of the prosthetic flavins exposes more cysteines in the more hydrophilic and hydrophobic regions of the peptide map, associating the former with FAD and the latter with FMN binding sites.

Adenine Nucleotides↗
PubMed1994

An exon-skipping mutation in the btk gene of a patient with X-linked agammaglobulinemia and isolated growth hormone deficiency.

X-linked agammaglobulinemia (XLA) is an inherited immunodeficiency disease associated with a block in differentiation from pre-B to B cells. The XLA gene encodes a 659 amino acids cytoplasmic protein tyrosine kinase named btk (Bruton's tyrosine kinase). The few btk gene alterations so far reported in XLA patients are heterogenous and distributed in all domains of the btk protein. They appear to be responsible for a range of B cell immunodeficiency disorders of variable severity. Rare families in which XLA is inherited together with isolated growth hormone deficiency (IGHD) have been reported. Genetic analysis has shown that this disease association maps to the same region of the X chromosome as XLA, but whether the two phenotypes are caused by a common or different developmental or biochemical mechanism is unknown. We have analyzed the btk gene of a patient with XLA and IGHD. RT-PCR analysis of btk transcripts, sequencing data obtained from cDNA and genomic DNA and in vitro splicing assays showed that an intronic point mutation (1882 + 5G-->A) is responsible for skipping of an exon located in the tyrosine kinase domain. This exon-skipping event results in a frameshift leading to a premature stop codon 14 amino acids downstream, and in the loss of the last 61 residues of the carboxy-terminal end of the protein. Although we studied a sporadic case, the results suggest that an alteration of the btk gene might cause this unusual phenotype.

Agammaglobulinaemia Tyrosine Kinase↗
PubMed1990

Pressor responses in rats following intravenous dynorphin A(1-13) administration are blocked by AVP-V1 receptor antagonism.

Hemodynamic (blood pressure and heart rate) experiments were conducted in conscious and/or anesthetized male Sprague-Dawley (S.D.), heterozygous and homozygous Brattleboro rats given intravenous (iv) dynorphin A(1-13), arginine vasopressin (AVP), norepinephrine (HCl, (NE) or sterile saline before and 10 min after an iv bolus injection of a specific receptor antagonist. These receptor blockers (kappa receptor antagonist Mr2266, alpha adrenoceptor antagonist phentolamine HCl or the AVP-V1 receptor antagonist d(CH2)5Tyr-(Me)AVP were given in equimolar concentrations (15 nmol/kg iv). In all conscious S.D. groups, iv injection of AVP (60 pmol/kg), NE (12.5 nmol/kg) and dynorphin A(1-13) (60 nmol/kg) evoked significant increases in mean arterial pressure (MAP) associated with concomitant bradycardia. The hemodynamic responses to 'both' AVP and dynorphin A(1-13) were blocked if given subsequent to AVP-V1 administration but not following phentolamine or Mr2266 pretreatment. The pressor and bradycardic responses of conscious heterozygous and homozygous Brattleboro rats after iv AVP or dynorphin again were only blocked by the AVP-V1 receptor antagonist. Anesthetized heterozygous and homozygous Brattleboro rats again showed pressor responses following iv AVP, NE or dynorphin A(1-13) but with slight or no associated bradycardia. The rise in blood pressure with AVP 'and' dynorphin A(1-13) in these groups also was only blocked by the d(CH2)5Tyr(Me)AVP antagonist. The results indicate that the pressor responses of rats given intravenous dynorphin A(1-13) involve the interaction of AVP-V1 receptors and suggest a functional interaction of these two neuropeptides in the modulation of vascular tone.

Angiotensin Receptor Antagonists↗
PubMed2005

Genome-wide scan for myopia in the Old Order Amish.

PURPOSE: To identify myopia susceptibility genes influencing common myopia in 34 Old Order Amish families, a genetically well-defined founder population. DESIGN: A prospective study of families with myopia consisting of a minimum of two individuals affected with myopia. METHODS: Extended families consisting of at least two siblings affected with myopia were ascertained. A genome-wide linkage scan using 387 markers was conducted by the Center for Inherited Disease Research (CIDR). Linkage analyses were conducted with parametric (autosomal dominant, fixed penetrance model) and nonparametric methods. Model-free linkage analysis was also performed maximizing over penetrance and over dominance (that is, fitting a wide range of both dominant and recessive models). RESULTS: Under the fixed penetrance model, the maximum two-point heterogeneity LOD score (HLOD) was 1.59 at D20S451 and the maximum multipoint HLOD was 1.92 at D6S1021. The nonparametric maximum multipoint (NPL) at D3S2427 had a P-value of .0005. Under the model-free analysis, multipoint heterogeneity LOD scores of 2.03 were observed on both chromosomes 8 (under a recessive model between D8S1130 and D8S1106) and X (under a recessive model between DXS6800 and DXS6789). Reanalyses of chromosomes 3, 6, 8, 20, and X using the best penetrance models resulted in maximum multipoint HLODs of 1.84 at D3S3053; 1.84 at D3S2427; 2.04 at D8S1130; and 2.34 at DXS6800. CONCLUSIONS: The locus on chromosome 8p23 independently confirms a report by Hammond and associates mapping a myopia quantitative trait loci (QTL) to this region.

Adolescent↗
PubMed2005

Kinetics of pyrophosphate-driven proton uptake by acidocalcisomes of Leptomonas wallacei.

In this work, we show the kinetics of pyrophosphate-driven H+ uptake by acidocalcisomes in digitonin-permeabilized promastigotes of Leptomonas wallacei. The vacuolar proton pyrophosphatase activity was optimal in the pH range of 7.5-8.0, was inhibited by imidiodiphosphate, and was completely dependent on K+ and PPi. H+ was released with the addition of Ca2+, suggesting the presence of a Ca2+/H+ antiport. In addition, X-ray elemental mapping associated with energy-filtering transmission electron microscopy showed that most of the Ca, Na, Mg, P, K, Fe, and Zn were located in acidocalcisomes. L. wallacei immunolabeled with antibodies against Trypanosoma cruzi pyrophosphatase show intense fluorescence in cytoplasmatic organelles of size and distribution similar to the acidocalcisomes. Altogether, the results show that L. wallacei acidocalcisomes possess a H+-pyrophosphatase with characteristics of type I V-H+-PPase. However, we did not find any evidence, either for the presence of H+-ATPases or for Na+/H+ exchangers in these acidocalcisomes.

Animals↗