Independent Subfamily Research Articles

Phylogeny of the Genus <i>Eleginus</i> (Gadidae) according to the Analysis of the Variability of Microsatellite Locus and mtDNA <i>CO1</i> Fragment

Genetic methods based on the study of the variability of mitochondrial (CO1) and nuclear (microsatellites) DNA were used to study the processes of morphogenesis in the genus Eleginus. The revealed level of genetic differentiation characterizes the Pacific Saffron cod (Eleginus gracilis) and Navaga (Eleginus nawaga) as independent species that diverged in a relatively recent period at the boundary of the Pliocene and Pleistocene. The White Sea Navaga’s populations were by microsatellites markers differed from the Navaga inhabiting the basins of the Kara and the Barents seas. At the same time, it is assumed that the Kara-Barents Sea region could act as a “glacial refugium”, which ensured the post-glacial settlement of Navaga, including in the “watered” White Sea depression. Phylogenetic analysis based on CO1 haplotypes diversity reveals demand of possible reorganization in order Gadiformes, including Eleginus in an independent subfamily – sister in relation to the subfamilies Gadinae, Lotinae, Merlucciinae. The prospects of improving genetic methodological approaches in the framework of the development of research on Saffron cod are noted.

Constitutively active B2 Raf-like kinases are required for drought-responsive gene expression upstream of ABA-activated SnRK2 kinases

Osmotic stresses, such as drought and high salinity, adversely affect plant growth and productivity. The phytohormone abscisic acid (ABA) accumulates in response to osmotic stress and enhances stress tolerance in plants by triggering multiple physiological responses through ABA signaling. Subclass III SNF1-related protein kinases 2 (SnRK2s) are key regulators of ABA signaling. Although SnRK2s have long been considered to be self-activated by autophosphorylation after release from PP2C-mediated inhibition, they were recently revealed to be activated by two independent subfamilies of group B Raf-like kinases, B2-RAFs and B3-RAFs, under osmotic stress conditions. However, the relationship between SnRK2 phosphorylation by these RAFs and SnRK2 autophosphorylation and the individual physiological roles of each RAF subfamily remain unknown. In this study, we indicated that B2-RAFs are constantly active and activate SnRK2s when released from PP2C-mediated inhibition by ABA-binding ABA receptors, whereas B3-RAFs are activated only under stress conditions in an ABA-independent manner and enhance SnRK2 activity. Autophosphorylation of subclass III SnRK2s is not sufficient for ABA responses, and B2-RAFs are needed to activate SnRK2s in an ABA-dependent manner. Using plants grown in soil, we found that B2-RAFs regulate subclass III SnRK2s at the early stage of drought stress, whereas B3-RAFs regulate SnRK2s at the later stage. Thus, B2-RAFs are essential kinases for the activation of subclass III SnRK2s in response to ABA under mild osmotic stress conditions, and B3-RAFs function as enhancers of SnRK2 activity under severe stress conditions.

Iterated function systems with super-exponentially close cylinders II

Until recently, it was an important open problem in Fractal Geometry to determine whether there exists an iterated function system acting on $\mathbb{R}$ with no exact overlaps for which cylinders are super-exponentially close at all small scales. Iterated function systems satisfying these properties were shown to exist by the author and by Barany and Kaenmaki. In this paper we prove a general theorem on the existence of such iterated function systems within a parameterised family. This theorem shows that if a parameterised family contains two independent subfamilies, and the set of parameters that cause exact overlaps satisfies some weak topological assumptions, then the original family will contain an iterated function system satisfying the desired properties. We include several explicit examples of parameterised families to which this theorem can be applied.

Description of a metacercaria of a zoogonid trematode Steganoderma cf. eamiqtrema Blend and Racz, 2020 (Microphalloidea: Zoogonidae), with notes on the phylogenetic position of the genus Steganoderma Stafford, 1904, and resurrection of the subfamily Lecithostaphylinae Odhner, 1911.

Metacercariae of the zoogonid trematode Steganoderma cf. eamiqtrema ex crab Chionoecetes bairdi caught in the Sea of Okhotsk were described using morphological and molecular-genetic (ITS2 region, 28S rRNA and nd1 genes) data. These are the first molecular-genetic data for the genus Steganoderma. The studied trematodes differed from S. eamiqtrema in having a much larger body size. The phylogenetic analysis based on the 28S rRNA gene supported neither the current taxonomic hypothesis that Steganoderma belongs to the subfamily Lepidophyllinae nor the earlier views that the Steganodermatinae and the Lecithostaphylinae are synonymous. The topology of the phylogenetic tree shows that the Steganodermatinae and the Lecithostaphylinae are independent subfamilies. However, morphological differences between them are obscure. Until morphological evidence for the Steganodermatinae is found, we propose to distinguish the subfamily Lepidophyllinae sensu stricto with the genera Lepidophyllus and Urinatrema, and the subfamily Lecithostaphylinae sensu lato uniting all the other former lepidophyllines. Thus, for now, we propose to consider the Steganodermatinae as a conditional synonym for Lecithostaphylinae sensu lato.

Contribution to the molecular phylogeny of Sciaridae (Diptera) with special attention to the genera emBradysia/em and emCorynoptera/em.

The systematics of the dipteran family Sciaridae is based mainly on morphological characters and has remained quite controversial. In this study, we used two mitochondrial DNA markers (CO1, 16S) and a nuclear one (28S) to take a glimpse into phylogenetic relationships of part of the North and Central European Sciaridae. A total of 91 species from 19 genera were analysed using Maximum Likelihood based phylogenetics (depending on the availability of valid sequences, 50-70 per gene). We strengthen the suggestion of the Chaetosciara group as an independent subfamily. Within the subfamily Megalosphyinae, two separate Bradysia clades were identified, suggesting a close relation between the genera Zygoneura, Austrosciara, and Scatopsciara. The genus Alpinosciara gen. n. is established to place the species of the former Corynoptera crassistylata group inside the subfamily Megalosphyinae. This new genus now includes 22 species.

Chitinases Encoded in the Genomes of Acidobacteria: Origin and Evolution

Acidobacteria are one of the widespread and numerically abundant groups of prokaryotes in soils and peatlands. The functional potential of these microorganisms remains poorly understood due to the limited number of cultured and characterized representatives. Acidisarcina polymorpha SBC82 is the only acidobacterium for which the ability to use chitin as a source of nitrogen and carbon has been experimentally proven. The genome of strain SBC82 encodes six proteins from the GH18 glycoside hydrolase family; each of these proteins can be considered as a representative of an independent subfamily. The present bioinformatics study shows that one of these subfamilies contains an extensive group of hypothetical chitinases from the Acidobacteria. This functional annotation was done based on the close relationship with the experimentally characterized enzyme from the proteobacterium Xylella fastidiosa. As shown by phylogenetic analysis, the studied group of acidobacterial proteins originated due to lateral transfer of the ancestral gene from the Firmicutes. Acidobacteria subsequently served as a source for multiple lateral gene transfers to a number of bacterial phyla, including the Proteobacteria. Analysis of metagenomic datasets revealed a wide distribution of chitinase genes in acidobacteria that inhabit wetlands and permafrost soils of the temperate and subarctic climatic zones.

Genome-wide screening of the classical cadherin gene family and cadherin-1 expression response infected with streptococcus agalactiae in nile tilapia (oreochromis niloticus)

Classical cadherin gene family relies on calcium ions in playing an important role in adhesion between cells. However, comprehensive studies to identify classical cadherin gene families in Nile tilapia (Oreochromis niloticus) have not been conducted. In this study, 18 classical gene family members were screened from Nile tilapia using various bioinformatics methods. These screened cadherins were randomly scattered across eight different linkage groups and shared a conserved LDRE motif. A phylogenetic tree was constructed to explore the evolution of classical cadherin members. The result showed that all classical cadherins were clustered together to form an independent subfamily. In addition, MEME analysis indicated that almost all the screened cadherins had similar motif arrangements. Also, neural-cadherin has up to eight closely adjacent tandem trisomy motif repeats. Finally, the sequence characteristics of cadherin-1 (Oncdh1) associated with pathogen invasion were discussed. The open reading frame of Oncdh1 was 2052 bp, encoding sequences of 683 amino acids with three conserved domains: cadherin repeat-like domain, cadherin prodomain, and cadherin tandem repeat domain. Real-time PCR experiments were carried out to detect the expression pattern of Oncdh1 in head kidney, brain, intestine, and spleen after Streptococcus agalactiae infection. The results showed a significant induction or downregulation of the expression level of Oncdh1 compared with the control group. Overall, the findings of this study might provide a reference for further research on the function of classical cadherin family of Nile tilapia in the future.

Bacteria from Poorly Studied Phyla as a Potential Source of New Enzymes: β-Galactosidases from Planctomycetes and Verrucomicrobia

Here, we present a phylogenetic analysis of a large group of the nearest homologues of a β-galactosidase, recently cloned from a soil metagenome and representing a new family of glycoside hydrolases. These proteins form an independent subfamily of hypothetical β-galactosidases and are almost exclusively represented in bacteria of the poorly studied phyla Planctomycetes and Verrucomicrobia, as well as Bacteroidetes. The phylogenetic tree of this subfamily consists of eleven highly stable clusters of branches, probably resulting from a series of gene duplications. An analysis of the tree topology suggested that the corresponding genes first evolved in Planctomycetes and most gene duplications occurred within this phylum. Later, these genes spread to several other bacterial phyla through horizontal transfers, the most numerous being transfers to Verrucomicrobia. The genomes of most Planctomycetes contain multiple paralogues of these genes of a different origin: in some cases, the horizontal transfers played a key role, while in other cases gene duplications played a key role. The importance of poorly studied groups of prokaryotes as a source of novel glycoside hydrolases is discussed.

Complete Mitochondrial Genome of Papilio protenor (Lepidoptera, Papilionidae) and Implications for Papilionidae Taxonomy

The complete mitochondrial genome (mitogenome) of Papilio protenor (Lepidoptera: Papilionidae) was sequenced and annotated in this study. The mitogenome comprised a typical circular, double-stranded DNA molecule of 15,268 bp in length including 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 transfer RNA (tRNA) genes, and an A+T-rich region. The gene order and mitogenome orientation were similar to those of all known Papilionidae species. The nucleotide composition of the P. protenor mitogenome exhibits considerable A+T bias (80.5%) and the AT (−0.019) and GC (−0.231) skewness is slightly negative. All of the PCGs except for cytochrome c oxidase (COI) start with a canonical ATN start codon, whereas the COI gene is tentatively designated by the CGA codon. Of the 13 PCGs, 11 contain the complete stop codon TAA or TAG, whereas COI and COII were terminated with a single T nucleotide. All tRNAs exhibit the typical cloverleaf structure, except for tRNASer(AGN), which does not contain the dihydrouridine arm. The 458 bp A+T-rich region is comprised of nonrepetitive sequences including the motif ATAGA followed by a poly-T stretch and a microsatellite-like (AT)6 element preceded by the ATTTA motif. Phylogenetic analysis of the 13 PCGs data using Bayesian inference, maximum likelihood methods, and maximum parsimony support the view that the subfamily Parnassiinae is regarded as an independent subfamily within Papilionidae and that Zerynthiini should be treated as one of the two clades of the subfamily Parnassiinae along with Parnasiini. In addition, the analysis strongly supports the monophyly of the subfamily Parnassiinae.

Phylogenetic relationships of corallinaceae (Corallinales, Rhodophyta): taxonomic implications for reef-building corallines.

A new, more complete, five-marker (SSU, LSU, psbA, COI, 23S) molecular phylogeny of the family Corallinaceae, order Corallinales, shows a paraphyletic grouping of seven well-supported monophyletic clades. The taxonomic implications included the amendment of two subfamilies, Neogoniolithoideae and Metagoniolithoideae, and the rejection of Porolithoideae as an independent subfamily. Metagoniolithoideae contained Harveylithon gen. nov., with H.rupestre comb. nov. as the generitype, and H.canariense stat. nov., H.munitum comb. nov., and H.samoënse comb. nov. Spongites and Pneophyllum belonged to separate clades. The subfamily Neogoniolithoideae included the generitype of Spongites, S.fruticulosus, for which an epitype was designated. Pneophyllum requires reassesment. The generitype of Hydrolithon, H.reinboldii, was a younger heterotypic synonym of H.boergesenii. The evolutionary novelty of the subfamilies Hydrolithoideae, Metagoniolithoideae, and Lithophylloideae was the development of tetra/bisporangial conceptacle roofs by filaments surrounding and interspersed among the sporangial initials.

The complete mitochondrial genome of Aix galericulata and Tadorna ferruginea: bearings on their phylogenetic position in the Anseriformes.

Aix galericulata and Tadorna ferruginea are two Anatidae species representing different taxonomic groups of Anseriformes. We used a PCR-based method to determine the complete mtDNAs of both species, and estimated phylogenetic trees based on the complete mtDNA alignment of these and 14 other Anseriforme species, to clarify Anseriform phylogenetics. Phylogenetic trees were also estimated using a multiple sequence alignment of three mitochondrial genes (Cyt b, ND2, and COI) from 68 typical species in GenBank, to further clarify the phylogenetic relationships of several groups among the Anseriformes. The new mtDNAs are circular molecules, 16,651 bp (Aix galericulata) and 16,639 bp (Tadorna ferruginea) in length, containing the 37 typical genes, with an identical gene order and arrangement as those of other Anseriformes. Comparing the protein-coding genes among the mtDNAs of 16 Anseriforme species, ATG is generally the start codon, TAA is the most frequent stop codon, one of three, TAA, TAG, and T-, commonly observed. All tRNAs could be folded into canonical cloverleaf secondary structures except for tRNASer (AGY) and tRNALeu (CUN), which are missing the "DHU" arm.Phylogenetic relationships demonstrate that Aix galericula and Tadorna ferruginea are in the same group, the Tadorninae lineage, based on our analyses of complete mtDNAs and combined gene data. Molecular phylogenetic analysis suggests the 68 species of Anseriform birds be divided into three families: Anhimidae, Anatidae, and Anseranatidae. The results suggest Anatidae birds be divided into five subfamilies: Anatinae, Tadorninae, Anserinae, Oxyurinae, and Dendrocygninae. Oxyurinae and Dendrocygninae should not belong to Anserinae, but rather represent independent subfamilies. The Anatinae includes species from the tribes Mergini, Somaterini, Anatini, and Aythyini. The Anserinae includes species from the tribes Anserini and Cygnini.

The Wall-associated Kinase gene family in rice genomes

The environment is a dynamic system in which life forms adapt. Wall-Associated Kinases (WAK) are a subfamily of receptor-like kinases associated with the cell wall. These genes have been suggested as sensors of the extracellular environment and triggers of intracellular signals. They belong to the ePK superfamily with or without a conserved arginine before the catalytic subdomain VIB, which characterizes RD and non-RD WAKs. WAK is a large subfamily in rice. We performed an extensive comparison of WAK genes from A. thaliana (AtWAK), O. sativa japonica and indica subspecies (OsWAK). Phylogenetic studies and WAK domain characterization allowed for the identification of two distinct groups of WAK genes in Arabidopsis and rice. One group corresponds to a cluster containing only OsWAKs that most likely expanded after the monocot–dicot separation, which evolved into a non-RD kinase class. The other group comprises classical RD-kinases with both AtWAK and OsWAK representatives. Clusterization analysis using extracellular and kinase domains demonstrated putative functional redundancy for some genes, but also highlighted genes that could recognize similar extracellular stimuli and activate different cascades. The gene expression pattern of WAKs in response to cold suggests differences in the regulation of the OsWAK genes in the indica and japonica subspecies. Our results also confirm the hypothesis of functional diversification between A. thaliana and O. sativa WAK genes. Furthermore, we propose that plant WAKs constitute two evolutionarily related but independent subfamilies: WAK-RD and WAK-nonRD. Recognition of this structural division will further provide insights to understanding WAK functions and regulations.

Exploring New CGRP Family Peptides and their Receptors in Vertebrates

Vertebrates have expanded their habitats from aquatic to terrestrial environments, which has accompanied the evolution of cardiovascular and osmoregulatory hormones. Specifically, mammals have developed mechanisms to maintain high blood pressure and blood volume, while extant fishes have developed hypotensive and Na-extruding mechanisms to adapt to the marine environment where they underwent a vast diversification. The CGRP family is one of the hormone systems that decrease blood pressure and blood volume. Within the CGRP family of teleost fishes, we found that adrenomedullins (AMs) have diversified and five paralogs (AM1-5) form an independent subfamily. Based on this discovery in fishes, we found AM2 and AM5 in mammals. In mammalian species that have AM2 and/or AM5, the peptides assume greater importance in the case of pathophysiological disturbances in pressure and fluid balance such as hypertension and cardiac and renal failure. In addition, novel functions of AM peptides have been suggested by the discovery of AM2 and AM5 in mammals. Current research on the CGRP family is focused on the identification of new receptors for AM2/AM5 and the establishment of AM2 knockout mice, which will enable new developments in the basic and clinical research on this intriguing hormone family. Importantly, comparative fish studies can contribute to new developments in our understanding of the function of the AM peptides.

The Complete Mitochondrial Genome of Bean Goose (Anser fabalis) and Implications for Anseriformes Taxonomy

Mitochondrial DNA plays an important role in living organisms, and has been used as a powerful molecular marker in a variety of evolutionary studies. In this study, we determined the complete mtDNA of Bean goose (Anser fabalis), which is 16,688 bp long and contains 13 protein-coding genes, 2 rRNAs, 22 tRNAs and a control region. The arrangement is similar to that of typical Anseriform species. All protein-coding genes, except for Cyt b, ND5, COI, and COII, start with an ATG codon. The ATG start codon is also generally observed in the 12 other Anseriform species, including 2 Anser species, with sequenced mitochondrial genomes. TAA is the most frequent stop codon, one of three–TAA, TAG, and T- –commonly observed in Anseriformes. All tRNAs could be folded into canonical cloverleaf secondary structures except for tRNASer(AGY) and tRNALeu(CUN), which are missing the dihydrouridine (DHU) arm. The control region of Bean goose mtDNA, with some conserved sequence boxes, such as F, E, D, and C, identified in its central domain. Phylogenetic analysis of complete mtDNA data for 13 Anseriform species supports the classification of them into four major branches: Anatinae, Anserinae, Dendrocygninae and Anseranatidae. Phylogenetic analyses were also conducted on 36 Anseriform birds using combined Cyt b, ND2, and COI sequences. The results clearly support the genus Somateria as an independent lineage classified in its own tribe, the Somaterini. Recovered topologies from both complete mtDNA and combined DNA sequences strongly indicate that Dendrocygninae is an independent subfamily within the family Anatidae and Anseranatidae represents an independent family. Based on the results of this study, we conclude that combining ND2, Cyt b, and COI sequence data is a workable solution at present for resolving phylogenetic relationships among Anseriform species in the absence of sufficient complete mtDNA data.

Abstracts of the 17th International Symposium on Bioluminescence and Chemiluminescence ‐ (ISBC 2012)

WARNING : The light-emitting molecular structures responsible for the chemiluminescence and fluorescence phenomena are not necessarily the same!

A new blue-shifted luciferase from the Brazilian Amydetes fanestratus (Coleoptera: Lampyridae) firefly: molecular evolution and structural/functional properties

Firefly luciferases usually produce bioluminescence in the yellow-green region, with colors in the green and yellow-orange extremes of the spectrum being less common. Several firefly luciferases have already been cloned and sequenced, and site-directed mutagenesis studies have already identified important regions and residues for bioluminescence colors. However the structural determinants and mechanisms of bioluminescence colors turned out to be elusive, mainly when comparing luciferases with a high degree of divergence. Thus comparison of more similar luciferases producing colors in the two extremes of the spectrum could be revealing. The South-American fauna of fireflies remains largely unstudied, with some unique taxa that are not found anywhere else in the world and that produce a wide range of bioluminescence colors. Among them, fireflies of the genus Amydetes are especially interesting because its taxonomical status as an independent subfamily or as a tribe is not yet solved, and because they usually produce a continuous bright blue-shifted bioluminescence. In this work we cloned the cDNA for the luciferase of the Atlantic rain forest Amydetes fanestratus firefly, which is found near Sorocaba municipality (São Paulo, Brazil). Despite showing a higher degree of identity with the South-American Cratomorphus, the European Lampyris and the Asiatic Pyrocoelia, phylogenetical analysis of the luciferase sequence support the inclusion of Amydetes as an independent subfamily. Amydetes luciferase displays one of the most blue-shifted emission spectra (λ(max) = 538 nm) among beetle luciferases, with lower pH-sensitivity and higher affinity for ATP when compared to other luciferases, making this luciferase attractive for sensitive ATP and reporter assays.

Na+-translocating Membrane Pyrophosphatases Are Widespread in the Microbial World and Evolutionarily Precede H+-translocating Pyrophosphatases

Membrane pyrophosphatases (PPases), divided into K(+)-dependent and K(+)-independent subfamilies, were believed to pump H(+) across cell membranes until a recent demonstration that some K(+)-dependent PPases function as Na(+) pumps. Here, we have expressed seven evolutionarily important putative PPases in Escherichia coli and estimated their hydrolytic, Na(+) transport, and H(+) transport activities as well as their K(+) and Na(+) requirements in inner membrane vesicles. Four of these enzymes (from Anaerostipes caccae, Chlorobium limicola, Clostridium tetani, and Desulfuromonas acetoxidans) were identified as K(+)-dependent Na(+) transporters. Phylogenetic analysis led to the identification of a monophyletic clade comprising characterized and predicted Na(+)-transporting PPases (Na(+)-PPases) within the K(+)-dependent subfamily. H(+)-transporting PPases (H(+)-PPases) are more heterogeneous and form at least three independent clades in both subfamilies. These results suggest that rather than being a curious rarity, Na(+)-PPases predominantly constitute the K(+)-dependent subfamily. Furthermore, Na(+)-PPases possibly preceded H(+)-PPases in evolution, and transition from Na(+) to H(+) transport may have occurred in several independent enzyme lineages. Site-directed mutagenesis studies facilitated the identification of a specific Glu residue that appears to be central in the transport mechanism. This residue is located in the cytoplasm-membrane interface of transmembrane helix 6 in Na(+)-PPases but shifted to within the membrane or helix 5 in H(+)-PPases. These results contribute to the prediction of the transport specificity and K(+) dependence for a particular membrane PPase sequence based on its position in the phylogenetic tree, identity of residues in the K(+) dependence signature, and position of the membrane-located Glu residue.

Induction of the SUMO-specific Protease 1 Transcription by the Androgen Receptor in Prostate Cancer Cells

Prostate cancer, the most frequently diagnosed carcinoma in males, is readily modulated via the transcriptional activity of androgen receptors. Our recent publication reported that androgen receptor-dependent transcription is significantly elevated with expression of the human sentrin/SUMO-specific protease (SENP1) in the androgen-sensitive human prostate cancer cell line (LNCaP). In situ hybridization studies indicated an elevation of SENP1 message in prostatic intraepithelial neoplasia and prostate cancer lesions as compared with normal prostate epithelia. This study aimed to delineate the mechanism for the regulation of SENP1 message and to determine the pathophysiological consequence of SENP1 induction with respect to prostate cancer. Real-time PCR confirmed the elevation of SENP1 mRNA in prostate cancer cells as compared with normal prostate epithelial cells. Chronic androgen exposure of LNCaP cells prompted an enhancement in the SENP1 transcript selectively. This androgen-mediated augmentation of SENP1 was absent with co-administration of the androgen receptor antagonist bicalutamide and in androgen receptor-negative prostate cancer PC-3 cells, indicating an androgen receptor-dependent event. Activation of the androgen receptor was required for binding an identified androgen response element and positively regulating SENP1 promoter activity. Abrogation of elevated SENP1 mRNA in prostate cancer cells significantly decreased androgen-mediated cell growth. Because increased SENP1 expression directly modulated androgen receptor-dependent cell proliferation and transcription, SENP1 could play an important role in prostate carcinogenesis.

Spatial and temporal expression of Zimp7 and Zimp10 PIAS-like proteins in the developing mouse embryo

ZIMP7 and ZIMP10 are two novel human PIAS-like proteins that share a similarity beyond the SP-RING Zn-finger domain that characterizes the PIAS family. This extended similarity is conserved in proteins of several other species and define an independent subfamily. ZIMP10 has been shown to increase the sumoylation of the androgen receptor (AR) leading to a stimulation of AR-mediated transcription. The Drosophila tonalli ( tna) is the ortholog gene of ZIMP7 and ZIMP10 and presents genetic interactions with the SWI–SNF complex. Mutations in the tna gene produce flies with homeotic phenotypes. In this study, we determined the spatial–temporal expression pattern of Zimp7 and Zimp10 in mouse embryos from embryonic day 7.5 (E7.5), to mid-gestation. We found that these two genes are extensively expressed during these embryonic days and present partially overlapping patterns with a predomination of the transcripts in the neural tissues at early stages and a drop of expression at E12.5. Unlike other PIAS proteins, the tonalli-related Zimp genes might be essential for development. Comparison of conserved motifs in Zimp7 and Zimp10 protein sequences identified characteristic family domains that might be related to their specific biological roles, besides their common role previously identified in the sumoylation pathway.

The phylogeny of native and exotic scallops cultured in China based on 16S rDNA sequences

Scallops of the Family Pectinidae are a valuable resource in marine industry of the world. Understanding the phylogeny of the family is important for the development of the industry. In this study, partial 16S mitochondrial rDNA genes were obtained from 8 scallop species that are commonly cultured indigenous and transplanted species in China. Phylogenetic relationships of Pectinidae were analyzed based on the 8 sequences and other 5 published ones in GenBank, representing 9 genera of the family. The molecular phylogeny trees were constructed using 3 methods with software PHYLIP. The results showe that total 13 species of scallops clustered in 4 clades. Pecten maximus joins P. jacobaeus then Amusium pleuronectes in cluster, indicating close relationship of genus Amusium with Pecten in evolution. P. yessoensis is close to Chlamys farreri and C. islandica. No enough material was available to single out genus Patinopecten as an independent monophyletic subfamily. The position of Adamussium colbecki indicates that it is far from genus Pecten but near to genus Chlamys in evolution.