Expression of <Emphasis Type="Italic">Pax group III</Emphasis> genes in the honeybee (<Emphasis Type="Italic">Apis mellifera</Emphasis>)

Pax group III genes are involved in a number of processes during insect segmentation. In Drosophila melanogaster, three genes, paired, gooseberry and gooseberry-neuro, regulate segmental patterning of the epidermis and nervous system. Paired acts as a pair-rule gene and gooseberry as a segment polarity gene. Studies of Pax group III genes in other insects have indicated that their expression is a good marker for understanding the underlying molecular mechanisms of segmentation. We have cloned three Pax group III genes from the honeybee (Apis mellifera) and examined their relationships to other insect Pax group III genes and their expression patterns during honeybee segmentation. The expression pattern of the honeybee homologue of paired is similar to that of paired in Drosophila, but its expression is modulated by anterior–posterior temporal patterning similar to the expression of Pax group III proteins in Tribolium. The expression of the other two Pax group III genes in the honeybee indicates that they also act in segmentation and nervous system development, as do these genes in other insects.     

Twenty four new microsatellite markers in two invasive pavement ants, <Emphasis Type="Italic">Tetramorium</Emphasis> sp.E and <Emphasis Type="Italic">T. tsushimae</Emphasis> (Hymenoptera: Formicidae)

Invasive species trigger biodiversity losses and alter ecosystem functioning, with life history shaping invasiveness (Sakai et al., Annu Rev Ecol Syst 32:305–332, 2001). However, pinpointing the relation of a specific life history to invasion success is difficult. One approach may be comparing congeners. The two Palearctic pavement ants, Tetramorium sp.E (widely known as T. caespitum, Schlick-Steiner et al., Mol Phylogenet Evol 40:259–273, 2006) and T. tsushimae have invaded North America (Steiner et al., Biol Invasions 8:117–123, 2006). Their life histories differ in that T. sp.E has separate single-queened colonies but T. tsushimae multi-queened colonies scattered over large areas (Sanada-Morimura et al., Insect Soc 53:141–148, 2006; Schlick-Steiner et al., Mol Phylogenet Evol 40:259–273, 2006; Steiner et al., Biol Invasions 8:117–123, 2006). Comparison of the genetic diversity in the entire native and non-native ranges will elucidate the invasion histories. Here, we present 13 and 11 microsatellites, developed for T. sp.E and T. tsushimae, respectively, and characterize all for both species. Florian M. Steiner, Wolfgang Arthofer and Birgit C. Schlick-Steiner contributed equally to this work.     

Validity of <Emphasis Type="Italic">Scolecenchelys aoki</Emphasis>, with a redescription of <Emphasis Type="Italic">Scolecenchelys gymnota</Emphasis> (Anguilliformes: Ophichthidae)

The myrophine ophichthid fishes (worm eels) Muraenichthys aoki Jordan and Snyder 1901 and Muraenichthys gymnotus Bleeker 1857 are redescribed as valid species of Scolecenchelys based on the types and non-type specimens collected from the Indo-Pacific. Because both species are similar to each other in having acute snouts, the posterior margin of the eye before the rictus, and their dorsal-fin origins located slightly posterior to a vertical line through the anus, Scolecenchelys aoki has usually been regarded as a junior synonym of Scolecenchelys gymnota. However, S. aoki is clearly distinguishable from S. gymnota by having a median groove on the ventral side of snout (absent in S. gymnota), uniserial maxillary teeth in smaller specimens (<200 mm TL; vs. biserial), three infraorbital sensory pores at postorbital area (vs. two), and more numerous vertebrae (56–65 in predorsal vs. 51–57; 53–58 in preanal vs. 47–52). Scolecenchelys aoki is restricted to Japanese waters and regarded as a senior synonym of Muraenichthys borealis Machida and Shiogaki 1990. Scolecenchelys gymnota is widely distributed in the Indo-Pacific, from South Africa and the Red Sea to Samoa, north to Okinawa, Japan. Sphagebranchus huysmani Weber 1913 and Muraenichthys fowleri Schultz 1943 are synonymized under S. gymnota.     

Abscisic acid levels in tomato ovaries are regulated by <Emphasis Type="Italic">LeNCED1</Emphasis> and <Emphasis Type="Italic">SlCYP707A1</Emphasis>

Although the hormones, gibberellin and auxin, are known to play a role in the initiation of fruits, no such function has yet been demonstrated for abscisic acid (ABA). However, ABA signaling and ABA responses are high in tomato (Solanum lycopersicum L.) ovaries before pollination and decrease thereafter (Vriezen et al. in New Phytol 177:60–76, 2008). As a first step to understanding the role of ABA in ovary development and fruit set in tomato, we analyzed ABA content and the expression of genes involved in its metabolism in relation to pollination. We show that ABA levels are relatively high in mature ovaries and decrease directly after pollination, while an increase in the ABA metabolite dihydrophaseic acid was measured. An important regulator of ABA biosynthesis in tomato is 9-cis-epoxy-carotenoid dioxygenase (LeNCED1), whose mRNA level in ovaries is reduced after pollination. The increased catabolism is likely caused by strong induction of one of four newly identified putative (+)ABA 8′-hydroxylase genes. This gene was named SlCYP707A1 and is expressed specifically in ovules and placenta. Transgenic plants, overexpressing SlCYP707A1, have reduced ABA levels and exhibit ABA-deficient phenotypes suggesting that this gene encodes a functional ABA 8′-hydroxylase. Gibberellin and auxin application have different effects on the LeNCED1 and SlCYP707A1 gene expression. The crosstalk between auxins, gibberellins and ABA during fruit set is discussed.     

Electron self-exchange and self-amplified posttranslational modification in the hemoglobins from <Emphasis Type="Italic">Synechocystis</Emphasis> sp. PCC 6803 and <Emphasis Type="Italic">Synechococcus</Emphasis> sp. PCC 7002

Many heme proteins undergo covalent attachment of the heme group to a protein side chain. Such posttranslational modifications alter the thermodynamic and chemical properties of the holoprotein. Their importance in biological processes makes them attractive targets for mechanistic studies. We have proposed a reductively driven mechanism for the covalent heme attachment in the monomeric hemoglobins produced by the cyanobacteria Synechococcus sp. PCC 7002 and Synechocystis sp. PCC 6803 (GlbN) (Nothnagel et al. in J Biol Inorg Chem 16:539–552, 2011). These GlbNs coordinate the heme iron with two axial histidines, a feature that distinguishes them from most hemoglobins and conditions their redox properties. Here, we uncovered evidence for an electron exchange chain reaction leading to complete heme modification upon substoichiometric reduction of GlbN prepared in the ferric state. The GlbN electron self-exchange rate constants measured by NMR spectroscopy were on the order of 10²–10³ M⁻¹ s⁻¹ and were consistent with the proposed autocatalytic process. NMR data on ferrous and ferric Synechococcus GlbN in solution indicated little dependence of the structure on the redox state of the iron or cross-link status of the heme group. This allowed the determination of lower bounds to the cross-exchange rate constants according to Marcus theory. The observations illustrate the ability of bishistidine hemoglobins to undergo facile interprotein electron transfer and the chemical relevance of such transfer for covalent heme attachment.     

The mechanism of sudden stripe formation during dorso-ventral patterning in <Emphasis Type="Italic">Drosophila</Emphasis>

The front and back (ventral and dorsal part respectively) of arthropods and chordates are defined by a highly conserved mechanism during early embryonic development [De Robertis and Kuroda in Annu. Rev. Cell Dev. Biol. 20, 285–308 (2004)]. An important feature is the sudden formation of a narrow midline peak of signaling. Mathematical models have helped to improve our understanding of the underlying mechanism [Eldar et al. in Nature 419(6904), 304–308 (2002); Mizutani in Dev. Cell 8(6), 915–924 (2005); Shimmi et al. in Cell 120(6), 873–886, (2005)]. In particular, the most recent model shows that diffusion and receptor-dependent degradation of the morphogen together with protease-mediated cleavage of a carrier protein for the morphogen are sufficient for the sudden generation of a sharp midline peak [Mizutani in Dev. Cell 8(6), 915–924 (2005)]. How these processes give rise to the observed pattern and how sensitive the model is to changes in parameter values has, however, not been resolved by this numerical study. By analysing the model in detail, we find that the sudden formation of a signaling peak is the consequence of the inversion of the gradient of the morphogen-carrier complex in the dorsal domain. As a consequence ligand is suddenly transported into rather than out of the midline, and a midline peak forms. We further show that a two-component carrier complex, consisting of Sog and Tsg, is required for abrupt peak formation. We derive quantitative conditions for the time and concentration at which the peak forms. We identify the receptor concentration, the ligand production and degradation rates, and the carrier production, diffusion, and cleavage rates as parameters to which the model is sensitive. Numerical studies confirm our analysis.      

The rat Ruby (<Emphasis Type="Italic">R</Emphasis>) locus is <Emphasis Type="Italic">Rab38</Emphasis>: identical mutations in Fawn-hooded and Tester-Moriyama rats derived from an ancestral Long Evans rat sub-strain

Hermansky-Pudlak syndrome (HPS) is a group of rare, recessive disorders in which oculocutaneous albinism, progressive pulmonary fibrosis, bleeding diathesis, and other abnormalities result from defective biogenesis of multiple cytoplasmic organelles. Seven different HPS genes are known in humans; in mouse, at least 16 loci are associated with HPS-like mutant phenotypes. In the rat, only two HPS models are known, Fawn-hooded (FH) and Tester Moriyama (TM), non-complementing strains in which HPS-like hypopigmentation and platelet storage pool deficiency result from a mutation of the Ruby (red eyed dilution; R) locus on Chromosome (Chr) 1. We have identified the R locus as the Rab38 gene, establishing that rat R is homologous to mouse chocolate (cht). Further, we show that FH and TM rats have identical Rab38 Met1Ile mutations, occurring on an identical Chr 1 marker allele haplotype, indicating that these two strains derive from a common ancestor. This ancestor appears to have been a sub-strain of the outbred Long Evans (LE) strain, and several modern LE sub-strains carry the Rab38 Met1Ile R mutation on the same Chr 1 marker haplotype. These findings have significant implications for the many past and ongoing studies that involve the FH and LE-derivative rat strains. Hermansky-Pudlak syndrome (HPS; MIM 203300) is a group of autosomal recessive diseases in which oculocutaneous albinism (OCA), progressive and fatal pulmonary fibrosis, and bleeding diathesis due to platelet storage pool deficiency result from defects in the biogenesis of specific cytoplasmic organelles and granules: melanosomes, lysosomes, and platelet dense granules (reviewed in Spritz 1999, 2000; Spritz et al. 2003). In humans, seven different HPS genes are known (Oh et al. 1996; DellAngelica et al. 1999; Anikster et al. 2001; Suzuki et al. 2002; Li et al. 2003; Zhang et al. 2003). In the mouse, at least 16 loci associated with HPS-like mutant phenotypes are known, seven of which are homologous to the human HPS loci (Swank et al. 1998; Bennett and Lamoreux 2003). The nucleotide sequence data reported in this paper have been submitted to GenBank and have been assigned the accession number AY425759. (Naoki Oiso) Present address: Department of Dermatology, Saiseikai Tondabayashi Hospital, Tondabayashi, Osaka 584-0082, Japan.     

Conserved and novel <Emphasis Type="Italic">Wnt</Emphasis> clusters in the basal eumetazoan <Emphasis Type="Italic">Nematostella vectensis</Emphasis>

Evolutionarily conserved gene clusters are interesting for two reasons: (1) they may illuminate ancient events in genome evolution and (2) they may reveal ongoing stabilizing selection; that is, the conservation of gene clusters may have functional significance. To test if the Wnt family of signaling factors exhibits conserved clustering in basal metazoans and if those clusters are of functional importance, we searched the genomic sequence of the sea anemone Nematostella vectensis for Wnt clusters and correlated the clustering we observed with published expression patterns. Our results indicate that the Wnt1–Wnt6–Wnt10 cluster observed in Drosophila melanogaster is partially conserved in the cnidarian lineage; Wnt6 and Wnt10 are separated by less than 4,500 nucleotides in Nematostella. A novel cluster comprised of Wnt5–Wnt7/Wnt7b was observed in Nematostella. Clustered Wnt genes do not exhibit Hox-like colinearity nor is the expression of linked Wnt genes more similar than the expression of nonlinked Wnt genes. Wnt6 and Wnt10 are not expressed in a spatially or temporally contiguous manner, and Wnt5 and Wnt7 are expressed in different germ layers.     

Purification of the photosynthetic reaction center from <Emphasis Type="Italic">Heliobacterium modesticaldum</Emphasis>

We have developed a purification protocol for photoactive reaction centers (HbRC) from Heliobacterium modesticaldum. HbRCs were purified from solubilized membranes in two sequential chromatographic steps, resulting in the isolation of a fraction containing a single polypeptide, which was identified as PshA by LC–MS/MS of tryptic peptides. All polypeptides reported earlier as unknown proteins (in Heinnickel et al., Biochemistry 45:6756–6764, 2006; Romberger et al., Photosynth Res 104:293–303, 2010) are now identified by mass spectrometry to be the membrane-bound cytochrome c ₅₅₃ and four different ABC-type transporters. The purified PshA homodimer binds the following pigments: 20 bacteriochlorophyll (BChl) g, two BChl g′, two 8¹-OH-Chl a _F, and one 4,4′-diaponeurosporene. It lacks the PshB polypeptide binding the F_A and F_B [4Fe–4S] clusters. It is active in charge separation and exhibits a trapping time of 23 ps, as judged by time-resolved fluorescence studies. The charge recombination rate of the P₈₀₀ ⁺F_X⁻ state is 10–15 ms, as seen before. The purified HbRC core was able to reduce cyanobacterial flavodoxin in the light, exhibiting a K _M of 10 μM and a k _cat of 9.5 s⁻¹ under near-saturating light. There are ~1.6 menaquinones per HbRC in the purified complex. Illumination of frozen HbRC in the presence of dithionite can cause creation of a radical at g = 2.0046, but this is not a semiquinone. Furthermore, we show that high-purity HbRCs are very stable in anoxic conditions and even remain active in the presence of oxygen under low light.     

Heterologous expression of <Emphasis Type="Italic">Arabidopsis</Emphasis><Emphasis Type="Italic">NPR1</Emphasis> (<Emphasis Type="Italic">AtNPR1</Emphasis>) enhances oxidative stress tolerance in transgenic tobacco plants

In Arabidopsis, NPR1 (non-expressor of pathogenesis related genes 1, AtNPR1) functions downstream of salicylic acid (SA) and modulates the SA mediated systemic acquired resistance. It is also involved in a cross talk with the jasmonate pathway that is essential for resistance against herbivores and necrotrophic pathogens. Overexpression of AtNPR1 in transgenic plants resulted in enhanced disease resistance. Recently, tobacco transgenic plants expressing AtNPR1 were shown to be tolerant to the early instars of Spodoptera litura (Meur et al., Physiol Plant 133:765–775, 2008). In this communication, we show that the heterologous expression of AtNPR1 in tobacco has also enhanced the oxidative stress tolerance. The transgenic plants exhibited enhanced tolerance to the treatment with methyl viologen. This tolerance was associated with the constitutive upregulation of PR1, PR2 (glucanase), PR5 (thaumatin like protein), ascorbate peroxidase (APX) and Cu²⁺/Zn²⁺ superoxide dismutase (SOD). This is the first demonstration of the novel function of heterologous expression of AtNPR1 in oxidative stress tolerance in transgenic tobacco.     

Mechanisms of age-specific regulation of dopamine metabolism by juvenile hormone and 20-hydroxyecdysone in <Emphasis Type="Italic">Drosophila</Emphasis> females

20-hydroxyecdysone (20E) and the juvenile hormone (JH) have an age-specific effect on total dopamine (DA) content in Drosophila (Gruntenko and Rauschenbach 2008). Earlier we studied the mechanism of influence of 20E and JH on DA metabolism in young females (Rauschenbach et al. in J Insect Physiol 53:587–591, 2007a: Arch Insect Biochem Physiol 65:95–102, 2008a; Gruntenko et al. in Arch Insect Biochem Physiol 72:263–269, 2009). Here we investigate the effects of 20E and JH on the activities of the alkaline phosphatase (ALP), tyrosine hydroxylase (TH) and DA-dependent arylalkylamine N-acetyltransferase (AANAT) in mature females of wild type D. virilis under normal conditions and under heat stress (38°C). 20E feeding of the flies led to a substantial decrease in ALP and TH activities and to an increase in AANAT activity in mature females. JH application resulted in an increasing of ALP and TH activities, but did not influence AANAT activity in mature females. A rise in JH and 20E levels was found to change ALP and TH stress reactivities. Mechanisms of age-specific regulation of DA level by 20E and JH in Drosophila females are discussed.     

Fine mapping of <Emphasis Type="Italic">qSTV11</Emphasis><Superscript><Emphasis Type="Italic">TQ</Emphasis></Superscript>, a major gene conferring resistance to rice stripe disease

The indica rice cultivar, Teqing, shows a high level of resistance to rice stripe virus (RSV). It is believed that this resistance is controlled by the gene, qSTV11 ^TQ . For positional cloning of the resistance gene, a set of chromosome single segment substitution lines (CSSSLs) was constructed, all of which had the genetic background of the susceptible japonica cultivar, Lemont, with different single substituted segments of Teqing on chromosome 11. By identifying the resistance of the CSSSLs-2006 in a field within a heavily diseased area, the resistance gene qSTV11 ^TQ was mapped between the markers Indel7 and RM229. Furthermore, in that region, six new markers were developed and 52 subregion CSSSLs (CSSSLs-2007) were constructed. The natural infection experiment was conducted again at different sites, with two replicates used in each site in order to identify the resistance phenotypes of the CSSSLs-2007 and resistant/susceptible controls in 2007. Through the results of 2007, qSTV11 ^TQ was localized in a region defined by the markers, CAPs1 and Indel4. In order to further confirm the position of qSTV11 ^TQ , another set of subregion CSSSLs (CSSSLs-2009) was constructed. Finally, qSTV11 ^TQ was localized to a 55.7 kb region containing nine annotated genes according to the genome sequence of japonica Nipponbare. The relationship between qSTV11 ^TQ and Stvb-i (Hayano-Saito et al. in Theor Appl Genet 101:59–63, 2000) and the reliability of the markers used on both sides of qSTV11 ^TQ for marker-assisted breeding of resistance to rice stripe disease are discussed.     

Developmental defects and seedling lethality in apyrase <Emphasis Type="Italic">AtAPY1</Emphasis> and <Emphasis Type="Italic">AtAPY2</Emphasis> double knockout mutants

Previously it was shown that the Arabidopsis apyrase genes AtAPY1 and AtAPY2 are crucial for male fertility because mutant pollen (apy1-1; apy2-1) with T-DNA insertions in both genes could not germinate (Steinebrunner et al. (2003) Plant Physiol. 131: 1638–1647). In this study, pollen germination was restored and apyrase T-DNA double knockouts (DKO) apy1-1/apy1-1; apy2-1/apy2-1 were generated by complementation with AtAPY2 under the control of a pollen-specific promoter. The DKO phenotype displayed developmental defects including the lack of functional root and shoot meristems. In cotyledons, morphogenetic and patterning abnormalities were apparent, e.g., unlobed pavement cells and stomatal clusters. Another set of lines was created which carried either AtAPY1 or AtAPY2 under a dexamethasone-(DEX)-inducible promoter as an additional transgene to the pollen-specific gene construct. Application of DEX did not reverse the DKO phenotype to wild-type, but some inducible lines exhibited less severe defects even in the absence of the inducer, probably due to some background expression. However, even these DKO mutants were seedling-lethal and shared other defects regarding cell division, cell expansion and stomatal patterning. Taken together, the defects in the DKO mutants demonstrate that AtAPY1 and AtAPY2 are essential for normal plant development.     

A new species of <Emphasis Type="Italic">Penopus</Emphasis> (Teleostei: Ophidiidae) from the Ryukyu Trench,the West Pacific,with remarks on <Emphasis Type="Italic">Penopus microphthalmus</Emphasis>

The bathyal genus Penopus (Ophidiidae) is revised based on 23 specimens. One specimen from the Ryukyu Trench represents a new species, Penopus japonicus. The remaining 22 specimens were found on both sides of the Atlantic Ocean, and neither 28 meristic and morphometric characters nor several morphological characters show any differences between the two populations. This supports Séret (1988), who considered Penopus macdonaldi Goode and Bean 1896 a junior synonym of Penopus microphthalmus (Vaillant 1888). The new Japanese species can be separated from the Atlantic species by having fewer rays in the dorsal (117 vs. 135–158) and anal (89 vs. 106–122) fins, the squamation of the head restricted to the middle part of the preopercle versus the squamation covering the dorsum, preopercle and the opercle in part, a distinct spine behind the posterior nostril versus the spine hardly visible and 9 spines on the hind margin of the preopercle versus 4–7 spines.     

Indirect regeneration of the Cancer bush (<Emphasis Type="Italic">Sutherlandia frutescens</Emphasis> L.) and detection of <Emphasis Type="SmallCaps">l</Emphasis>-canavanine in <Emphasis Type="Italic">in vitro</Emphasis> plantlets using NMR

The present study reports a simple protocol for indirect shoot organogenesis and plant regeneration of Sutherlandia using rachis and stem segments. Different concentrations (0.0–68.08 μmol l⁻¹) of thidiazuron (TDZ) were used for callus induction and shoot organogenesis. The highest percentage of callus formation (97.5%) and the highest percentage of explants forming shoots (88.8%) were obtained from rachis explants cultured onto Murashige and Skoog (MS) medium (Murashige and Skoog, Physiol. Plant. 15:473–495, 1962) supplemented with 45.41 μmol l⁻¹ TDZ. Scanning electron microscopy demonstrated the early development of adventitious shoots derived from callus cultures. Shoot clusters were further developed and grown in MS hormone-free medium. The presence of l-canavanine was determined by thin-layer chromatography and confirmed after column fractionation using silica gel and nuclear magnetic resonance spectroscopy. Individual shoots were rooted on different concentrations and combinations of MS salt strength and IBA. Half-strength MS salt medium supplemented with 24.6 μmol l⁻¹ IBA was optimal for root induction in which 78% of shoots were rooted. The in vitro plants were successfully acclimatized in a growth chamber with a 90% survival rate.     

Kinetic models of photosystem II should accommodate the effect of donor side quenching on variable chlorophyll <Emphasis Type="Italic">a</Emphasis> fluorescence in the microseconds time range

Quantitative data on laser flash-induced variable fluorescence in the 100 ns to 1 ms time range (Belyaeva et al. in Photosynth Res 98:105–119, 2008) confirming those of others (Steffen et al. in Biochemistry 40:173–180, 2001, Biochemistry 44:3123–3132, 2005; Belyaeva et al. in Biophysics 51(6):976–990, 2006), need a substantial correction with respect to magnitude of the normalized variable fluorescence associated with single turnover-induced charge separation in RCs of PS II. Their data are conclusive with the involvement of donor side quenching, the release of which occurs with a rate constant in the range of tens of ms⁻¹, and presumed to be associated with reduction of Y_\textz ⁺ Y_{\text{z}}^{ + } by the OEC.     

Expression of the <Emphasis Type="Italic">HEV2.1</Emphasis> gene promoter in transgenic <Emphasis Type="Italic">Hevea brasiliensis</Emphasis>

In this article we describe the identification of endophytic bacteria belonging to three groups isolated from shoot tip cultures of banana cv. Grand Naine in a recent study (Thomas et al. 2008) based on partial 16S rRNA gene sequence homology analysis. The first group included banana stocks that displayed obvious colony growth on MS based tissue culture medium during the first in vitro passage. The second group constituted stocks that were tissue index-negative for cultivable bacteria initially but turned index-positive after a few to several (4–8) in vitro passages while the third group formed one sub-stock that turned index-positive after about 18 passages. The organisms belonged to about 20 different genera comprising of α, β, γ-proteobacteria, Gram-positive firmicutes and actinobacteria. Visibly expressing easily cultured organisms during the first in vitro passage included Enterobacter, Klebsiella, Ochrobactrum, Pantoea, Staphylococcus and Bacillus spp. Organisms of second group that were not detected or non-culturable originally constituted Brevundimonas, Methylobacterium, Alcaligenes, Ralstonia, Pseudomonas, Corynebacterium, Microbacterium, Staphylococcus, Oceanobacillus and Bacillus spp. while the third group that turned cultivable after extended in vitro culturing included mostly non-filamentous actinobacteria (Brachybacterium, Brevibacterium, Kocuria and Tetrasphaera spp.). The identification results suggested that the endophytes of second and third groups were not strictly obligate or fastidious microbes but those surviving in viable but-non-culturable (VBNC) state and displaying gradual activation to cultivable form during continuous tissue culturing. Several of the organisms isolated are known as beneficial ones in agriculture while some organisms have possible implications in human health. The use of tissue cultures for isolating uncommon endophytes is discussed. Supply of live bacterial cultures or genetic material for research purpose is subject to their revival from glycerol stocks (as some of the organisms showed poor tolerance) and the requestor obtaining written permission from the Director General, Indian Council of Agricultural Research, New Delhi-110001.     

<Emphasis Type="Italic">Wnt</Emphasis> gene loss in flatworms

Wnt genes encode secreted glycoproteins that act in cell–cell signalling to regulate a wide array of developmental processes, ranging from cellular differentiation to axial patterning. Discovery that canonical Wnt/β-catenin signalling is responsible for regulating head/tail specification in planarian regeneration has recently highlighted their importance in flatworm (phylum Platyhelminthes) development, but examination of their roles in the complex development of the diverse parasitic groups has yet to be conducted. Here, we characterise Wnt genes in the model tapeworm Hymenolepis microstoma and mine genomic resources of free-living and parasitic species for the presence of Wnts and downstream signalling components. We identify orthologs through a combination of BLAST and phylogenetic analyses, showing that flatworms have a highly reduced and dispersed complement that includes orthologs of only five subfamilies (Wnt1, Wnt2, Wnt4, Wnt5 and Wnt11) and fewer paralogs in parasitic flatworms (5–6) than in planarians (9). All major signalling components are identified, including antagonists and receptors, and key binding domains are intact, indicating that the canonical (Wnt/β-catenin) and non-canonical (planar cell polarity and Wnt/Ca²⁺) pathways are functional. RNA-Seq data show expression of all Hymenolepis Wnts and most downstream components in adults and larvae with the notable exceptions of wnt1, expressed only in adults, and wnt2 expressed only in larvae. The distribution of Wnt subfamilies in animals corroborates the idea that the last common ancestor of the Cnidaria and Bilateria possessed all contemporary Wnts and highlights the extent of gene loss in flatworms.