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T Bisseling

Publications and source records attributed to T Bisseling.

At least 19 recordsLinked to original sources

Studies on the origin and structure of tubules made by the movement protein of Cowpea mosaic virus.

Cowpea mosaic virus (CPMV) moves from cell to cell by transporting virus particles via tubules formed through plasmodesmata by the movement protein (MP). On the surface of protoplasts, a fusion between the MP and the green fluorescent protein forms similar tubules and peripheral punctate spots. Here it was shown by time-lapse microscopy that tubules can grow out from a subset of these peripheral punctate spots, which are dynamic structures that seem anchored to the plasma membrane. Fluorescence resonance energy transfer experiments showed that MP subunits interacted within the tubule, where they were virtually immobile, confirming that tubules consist of a highly organized MP multimer. Fluorescence recovery after photobleaching experiments with protoplasts, transiently expressing fluorescent plasma membrane-associated proteins of different sizes, indicated that tubules made by CPMV MP do not interact directly with the surrounding plasma membrane. These experiments indicated an indirect interaction between the tubule and the surrounding plasma membrane, possibly via a host plasma membrane protein.

Cell Membrane↗

The movement protein of cowpea mosaic virus binds GTP and single-stranded nucleic acid in vitro.

The movement protein (MP) of Cowpea mosaic virus forms tubules in plasmodesmata to enable the transport of mature virions. Here it is shown that the MP is capable of specifically binding riboguanosine triphosphate and that mutational analysis suggests that GTP binding plays a role in the targeted transport of the MP. Furthermore, the MP is capable of binding both single-stranded RNA and single-stranded DNA in a non-sequence-specific manner, and the GTP- and RNA-binding sites do not overlap.

Animals↗

An integrated physical, genetic and cytogenetic map around the sunn locus of Medicago truncatula.

The sunn mutation of Medicago truncatula is a single-gene mutation that confers a novel supernodulation phenotype in response to inoculation with Sinorhizobium meliloti. We took advantage of the publicly available codominant PCR markers, the high-density genetic map, and a linked cytogenetic map to define the physical and genetic region containing sunn. We determined that sunn is located at the bottom of linkage group 4, where a fine-structure genetic map was used to place the locus within a approximately 400-kb contig of bacterial artificial chromosome (BAC) clones. Genetic analyses of the sunn contig, as well as of a second, closely linked BAC contig designated NUM1, indicate that the physical to genetic distance within this chromosome region is in the range of 1000 -1100 kb.cM-1. The ratio of genetic to cytogenetic distance determined across the entire region is 0.3 cM.microm(-1). These estimates are in good agreement with the empirically determined value of approximately 300 kb.microm(-1) measured for the NUM1 contig. The assignment of sunn to a defined physical interval should provide a basis for sequencing and ultimately cloning the responsible gene.

Chromosome Walking↗

Integration of the FISH pachytene and genetic maps of Medicago truncatula.

A molecular cytogenetic map of Medicago truncatula (2n = 2x = 16) was constructed on the basis of a pachytene DAPI karyogram. Chromosomes at this meiotic prophase stage are 20 times longer than at mitotic metaphase, and display a well differentiated pattern of brightly fluorescing heterochromatin segments. We describe here a pachytene karyogram in which all chromosomes can be identified based on chromosome length, centromere position, heterochromatin patterns, and the positions of three repetitive sequences (5S rDNA, 45S rDNA and the MtR1 tandem repeat), visualized by fluorescence in situ hybridization (FISH). We determined the correlation between genetic linkage groups and chromosomes by FISH mapping of bacterial artificial chromosome (BAC) clones, with two to five BACs per linkage group. In the cytogenetic map, chromosomes were numbered according to their corresponding linkage groups. We determined the relative positions of the 20 BACs and three repetitive sequences on the pachytene chromosomes, and compared the genetic and cytological distances between markers. The mapping resolution was determined in a euchromatic part of chromosome 5 by comparing the cytological distances between FISH signals of clones of a BAC contig with their corresponding physical distance, and showed that resolution in this region is about 60 kb. The establishment of this FISH pachytene karyotype, with a far better mapping resolution and detection sensitivity compared to those in the highly condensed mitotic metaphase complements, has created the basis for the integration of molecular, genetic and cytogenetic maps in M. truncatula.

Base Sequence↗

Integrated cytogenetic map of chromosome arm 4S of A. thaliana: structural organization of heterochromatic knob and centromere region.

We have constructed an integrated cytogenetic map of chromosome arm 4S of Arabidopsis thaliana. The map shows the detailed positions of various multicopy and unique sequences relative to euchromatin and heterochromatin segments. A quantitative analysis of the map positions at subsequent meiotic stages revealed a striking pattern of spatial and temporal variation in chromatin condensation for euchromatin and heterochromatin. For example, the centromere region consists of three domains with distinguishable structural, molecular, and functional properties. We also characterized a conspicuous heterochromatic knob of approximately 700 kb that accommodates a tandem repeat and several dispersed pericentromere-specific repeats. Moreover, our data provide evidence for an inversion event that relocated pericentromeric sequences to an interstitial position, resulting in the heterochromatic knob.

Arabidopsis↗

In vivo fluorescence correlation microscopy (FCM) reveals accumulation and immobilization of Nod factors in root hair cell walls.

Fluorescence correlation microscopy (FCM) is a new single-molecule detection technique based on the confocal principle to quantify molecular diffusion and concentration of fluorescent molecules (particles) with sub-micron resolution. In this study, FCM is applied to examine the diffusional behaviour of fluorescent Nod factor analogues on living Vicia sativa root hairs. Three recently described Nod factors with a fluorescent acyl chain (Goedhart et al. Biochemistry 1999, 38, 10898-10907) were used. Plasmolysis of fluorescently labelled root hairs showed that the Nod factors are predominantly located in the cell wall, as hardly any fluorescence could be detected in the plasma membrane. After Nod factor-induced root hair deformation, the new outgrowth was not labelled, indicating a lack of migration of Nod factors to the newly synthesized cell wall. In agreement, FCM showed a > 1,000-fold reduction of molecular mobility of the fluorescence Nod factors upon binding to the cell wall. In addition, FCM demonstrated that Nod factors, when exogenously applied in aqueous solution at 10 nM, markedly concentrate in the cell wall of root hairs (up to 50-fold). The feasibility of applying FCM for the study of living plant cells as well as the implications of our results for the perception of Nod factors are discussed.

Arabidopsis↗

Casuarina glauca prenodule cells display the same differentiation as the corresponding nodule cells.

Recent phylogenetic studies have implied that all plants able to enter root nodule symbioses with nitrogen-fixing bacteria go back to a common ancestor (D.E. Soltis, P.S. Soltis, D.R. Morgan, S.M. Swensen, B.C. Mullin, J.M. Dowd, and P.G. Martin, Proc. Natl. Acad. Sci. USA, 92:2647-2651, 1995). However, nodules formed by plants from different groups are distinct in nodule organogenesis and structure. In most groups, nodule organogenesis involves the induction of cortical cell divisions. In legumes these divisions lead to the formation of a nodule primordium, while in non-legumes they lead to the formation of a so-called prenodule consisting of infected and uninfected cells. Nodule primordium formation does not involve prenodule cells, and the function of prenodules is not known. Here, we examine the differentiation of actinorhizal prenodule cells in comparison to nodule cells with regard to both symbionts. Our findings indicate that prenodules represent primitive symbiotic organs whose cell types display the same characteristics as their nodule counterparts. The results are discussed in the context of the evolution of root nodule symbioses.

Actinomycetales↗

The evolution of nodulation.

In this review we will first describe the different steps leading to nodule formation, and these will be compared with processes of non-symbiotic plant development and growth. In general, aspects of both actinorhizal as well as rhizobial symbiosis are described, but in several cases, the emphasis will be on the Rhizobium-legume symbiosis because more knowledge of this system is available. Subsequently, the phylogeny of nodulating plants is described and a comparison is made between several aspects of legume and actinorhizal nodulation. At the end of this paper the relationship between nodule symbiosis and endomycorrhizal symbiosis is described, and it is discussed to what extent the development of root nodules involves unique properties, or whether processes and genes have been recruited from common plant development and the endomycorrhizal symbiosis.

Actinomycetales↗

Nod factors integrate spontaneously in biomembranes and transfer rapidly between membranes and to root hairs, but transbilayer flip-flop does not occur.

Three novel nodulation (Nod) factors were synthesized from chitotetraose and three structurally different fluorescent BODIPY-tagged fatty acids. With fluorescence spectroscopic and microscopic techniques, the following aspects were studied: whether these amphiphilic molecules insert in membranes, whether they transfer between different membranes, and whether they are able to transfer from a membrane to a legume root hair. Fluorescence correlation spectroscopy showed that fluorescent Nod factors are present as monomers in PBS buffer at a concentration of 10 nM, but that when either Triton X-100 micelles or dioleoylphosphatidylcholine (DOPC) vesicles are present, the Nod factors are associated with these particles. With time-correlated single-photon counting fluorescence spectroscopy, it was shown that upon Nod factor insertion in the membrane, the rotation of the fluorescent acyl chain was markedly reduced. A fluorescence resonance energy transfer assay was used to study the transfer of Nod factors from one membrane to the other, or from vesicles to root hairs. Nod factors transfer rapidly between membranes or from vesicles to root hair cell walls. However, they do not flip-flop between membrane leaflets. The results provide novel insights for the mode of secretion and transfer of Nod factors during the early steps of the Rhizobium-legume interaction.

Boron Compounds↗

The role of plant peptides in intercellular signalling.

Genetic, as well as biochemical, studies have now demonstrated that peptides, like in animals, play a role in signalling processes. In this review, the role of the four known peptides with signalling properties in the communication between cells and between organs is discussed.

Arabidopsis Proteins↗

Microspectroscopic imaging of nodulation factor-binding sites on living Vicia sativa roots using a novel bioactive fluorescent nodulation factor.

A novel bioactive fluorescent nodulation (Nod) factor, NodRlv-IV(BODIPY FL-C16), has been synthesized by attaching a BODIPY FL-C16 acyl chain to the primary amino group of chitotetraose deacetylated at the nonreducing terminus by recombinant NodB. The binding of the fluorescent Nod factor to root systems of Vicia sativa was investigated with fluorescence spectral imaging microscopy (FSPIM) and fluorescence ratio imaging microscopy (FRIM). Spatially resolved fluorescence spectra of living and labeled Vicia sativa root systems were measured by FSPIM. Strong autofluorescence, inherent to many plant systems when excited at 488 nm, was corrected for by utilizing the difference in fluorescence emission spectra of the autofluorescence and NodRlv-IV(BODIPY FL-C16). A methodology is presented to break down the in situ fluorescence emission spectra into spatially resolved autofluorescence and BODIPY FL fluorescence spectra. Furthermore, an FRIM method was developed for correcting autofluorescence in fluorescence micrographs for this system. After autofluorescence correction it was shown that NodRlv-IV(BODIPY FL-C16) was concentrated in the root hairs, but was also bound to other parts of the root surface.

Binding Sites↗

Nod factor-induced expression of leghemoglobin to study the mechanism of NH4NO3 inhibition on root hair deformation.

Nod factors secreted by Rhizobium leguminosarum by, viciae induce root hair deformation, the formation of nodule primordia, and the expression of early nodulin genes in Vicia sativa (vetch). Root hair deformation is induced within 3 h in a small, susceptible zone (+/-2 mm) of the root. NH4NO3, known to be a potent blocker of nodule formation, inhibits root hair deformation, initial cortical cell divisions, and infection thread formation. To test whether NH4NO3 affects the formation of a component of the Nod factor perception-transduction system, we studied Nod factor-induced gene expression. The differential display technique was used to search for marker genes, which are induced within 1 to 3 h after Nod factor application. Surprisingly, one of the isolated cDNA clones was identified as a leghemoglobin gene (VsLb1), which is induced in vetch roots within 1 h after Nod factor application. By using the drug brefeldin A, it was then shown that VsLb1 activation does not require root hair deformation. The pVsLb1 clone was used as a marker to show that in vetch plants grown in the presence of NH4NO3, Nod factor perception and transduction leading to gene expression are unaffected.

Base Sequence↗