Sex chromosome evolution in snakes inferred from divergence patterns of two gametologous genes and chromosome distribution of sex chromosome-linked repetitive sequences

Molecular phylogenic trees of CTNNB1 gene. This figure shows neighbor-joining trees of CTNNB1 gene with the long alignment for 20 tetrapod species and the short alignment for 26 squamate species. (PDF 289 kb

Highly Differentiated ZW Sex Microchromosomes in the Australian Varanus Species Evolved through Rapid Amplification of Repetitive Sequences

Transitions between sex determination systems have occurred in many lineages of squamates and it follows that novel sex chromosomes will also have arisen multiple times. The formation of sex chromosomes may be reinforced by inhibition of recombination and the accumulation of repetitive DNA sequences. The karyotypes of monitor lizards are known to be highly conserved yet the sex chromosomes in this family have not been fully investigated. Here, we compare male and female karyotypes of three Australian monitor lizards, Varanus acanthurus, V. gouldii and V. rosenbergi, from two different clades. V. acanthurus belongs to the acanthurus clade and the other two belong to the gouldii clade. We applied C-banding and comparative genomic hybridization to reveal that these species have ZZ/ZW sex micro-chromosomes in which the W chromosome is highly differentiated from the Z chromosome. In combination with previous reports, all six Varanus species in which sex chromosomes have been identified have ZZ/ZW sex chromosomes, spanning several clades on the varanid phylogeny, making it likely that the ZZ/ZW sex chromosome is ancestral for this family. However, repetitive sequences of these ZW chromosome pairs differed among species. In particular, an (AAT)n microsatellite repeat motif mapped by fluorescence in situ hybridization on part of W chromosome in V. acanthurus only, whereas a (CGG)n motif mapped onto the W chromosomes of V. gouldii and V. rosenbergi. Furthermore, the W chromosome probe for V. acanthurus produced hybridization signals only on the centromeric regions of W chromosomes of the other two species. These results suggest that the W chromosome sequences were not conserved between gouldii and acanthurus clades and that these repetitive sequences have been amplified rapidly and independently on the W chromosome of the two clades after their divergence

Effects of Media on Overcoming Vitrification of Carnation in Apex Culture

スプレータイプのカーネーション“ナティラ”と“ピンクカジノ”を供試し,茎頂培養に適した培地の支持体を検討した.基本培地としてハイポネックス,NH4NO3,MgSO4・7H20,Na-EDTA,塩酸ピリドキシン,カイネチン,NAA,しょ糖を含む培地に,支持体として寒天0.6% ,gelrite0.2% またはペーパーブリッジを別々に添加した.茎頂は0.3～0.5mmの部分を切り出し,培地に植え付けた.3か月培養の結果,寒天培地上で最も高率に正常な植物が生長し,gelrite上では最も水浸状の,しかも多芽体が多かった.生体重と乾燥重の比較では,gelrite,寒天,ペーパーブリッジの順であったが,乾物率は寒天が最も高く,gelriteは低かった

Vegetative Propagation of Yakon by Shoot Apex, Node and Callus Cultures

ヤーコンの無病苗の増殖のために,茎頂培養,節培養,カルス培養を試みた.茎頂培養は,0.01mg/l NAAとBAを添加したMS培地に0.3～0.5mmの茎頂を植え付けて約1か月間培養することにより,植物体となった.これはバーミキュライトで順化することが可能であった. 節培養は,葉を切り捨てた無菌植物の節を0.01mg/l NAA及びBA添加又は無添加のMS又はハイポネックス培地に植え付けることにより,節当たり約2苗条得ることができ,そのままの培地で培養することにより発根した.基部側の下半分の節からの苗条の生育が非常に良く,MS,ハイポネックスいずれの培地でもホルモン無添加培地でよく生育した. カルス培養は,供試材料として無菌植物の葉,茎,根を比較したところ茎で一番大きなカルスができたが,培地によっては再現性にかける.茎のみならず葉でも根でも0.lmg/l 2,4-DとBAを添加したMS培地で大きなカルスが出来た. 茎頂培養で形成された植物の茎頂を,0.1mg/l 2,4-Dと1mg/l BAを添加した培地に移植してカルスを形成させ,さらに0.1mg/l BA添加培地に移植したところ,低率ながら不定胚が形成された.これは植物体にまで生長した

Glycine cleavage system in neurogenic regions

The glycine cleavage system (GCS) is the essential enzyme complex for degrading glycine and supplying 5,10-methylenetetrahydrofolate for DNA synthesis. Inherited deficiency of this system causes non-ketotic hyperglycinemia, characterized by severe neurological symptoms and frequent association of brain malformations. Although high levels of glycine have been considered to cause the above-mentioned problems, the detailed pathogenesis of this disease is still unknown. Here we show that GCS is abundantly expressed in rat embryonic neural stem/progenitor cells in the neuroepithelium, and this expression is transmitted to the radial glia-astrocyte lineage, with prominence in postnatal neurogenic regions. These data indicate that GCS plays important roles in neurogenesis, and suggest that disturbance of neurogenesis induced by deficiency of GCS may be the main pathogenesis of non-ketotic hyperglycinemi

Current Treatment Strategies and Nanoparticle-Mediated Drug Delivery Systems for Pulmonary Arterial Hypertension

There are three critical pathways for the pathogenesis and progression of pulmonary arterial hypertension (PAH): the prostacyclin (prostaglandin I-2) (PGI(2)), nitric oxide (NO), and endothelin pathways. The current approved drugs targeting these three pathways, including prostacyclin (PGI(2)), phosphodiesterase type-5 (PDE5) inhibitors, and endothelin receptor antagonists (ERAs), have been shown to be effective, however, PAH remains a severe clinical condition and the long-term survival of patients with PAH is still suboptimal. The full therapeutic abilities of available drugs are reduced by medication, patient non-compliance, and side effects. Nanoparticles are expected to address these problems by providing a novel drug delivery approach for the treatment of PAH. Drug-loaded nanoparticles for local delivery can optimize the efficacy and minimize the adverse effects of drugs. Prostacyclin (PGI(2)) analogue, PDE5 inhibitors, ERA, pitavastatin, imatinib, rapamycin, fasudil, and oligonucleotides-loaded nanoparticles have been reported to be effective in animal PAH models and in vitro studies. However, the efficacy and safety of nanoparticle mediated-drug delivery systems for PAH treatment in humans are unknown and further clinical studies are required to clarify these points

Molecular cloning and nucleotide sequence of cDNA encoding the entire precursor of rat liver medium chain acyl coenzyme A dehydrogenase.

cDNA encoding the precursor of rat liver medium chain acyl-CoA dehydrogenase (EC 1.3.99.3) was cloned and sequenced. The longest cDNA insert isolated was 1866 bases in length. This cDNA encodes the entire protein of 421-amino acids including a 25-amino acid leader peptide and a 396-amino acid mature polypeptide. The identity of the medium chain acyl-CoA dehydrogenase clone was confirmed by matching the amino acid sequence predicted from the cDNA to the NH2-terminal and nine internal tryptic peptide sequences derived from pure rat liver medium chain acyl-CoA dehydrogenase. The calculated molecular masses of the precursor medium chain acyl-CoA dehydrogenase, the mature medium chain acyl-CoA dehydrogenase, and the leader peptide are 46,600, 43,700, and 2,900 daltons, respectively. The leader peptide contains five basic amino acids and only one acidic amino acid; thus, it is positively charged, overall. Cysteine residues are unevenly distributed in the mature portion of the protein; five of six are found within the NH2-terminal half of the polypeptide. Comparison of medium chain acyl-CoA dehydrogenase sequence to other flavoproteins and enzymes which act on coenzyme A ester substrates did not lead to unambiguous identification of a possible FAD-binding site nor a coenzyme A-binding domain. The sequencing of other homologous acyl-CoA dehydrogenases will be informative in this regard

Phase II clinical trial of sorafenib plus interferon-alpha treatment for patients with metastatic renal cell carcinoma in Japan

Comparison of the current study with other sorafenib-interferon combination studies and with single-agent sorafenib studies [25]. (XLSX 12 kb

Inhibitory effects of RAGE-aptamer on development of monocrotaline-induced pulmonary arterial hypertension in rats

Background: The receptor for advanced glycation end products (RAGE), a transmembrane receptor belonging to the immunoglobulin superfamily, is overexpressed in pulmonary artery smooth muscle cells (PASMCs) in patients with pulmonary arterial hypertension (PAH) and is implicated in the etiology of PAH. Recently, we reported that RAGE-aptamer, a short and single-stranded DNA directed against RAGE, inhibited an inappropriate increase in cultured PASMCs in PAH. The aim of this study was to determine the efficacy of RAGEaptamer in monocrotaline-induced PAH in rats. Methods and Results: Rats were assigned to either an untreated control group, a group that received continuous subcutaneous administration of RAGE-aptamer immediately after monocrotaline injection, or a group that received control-aptamer immediately after monocrotaline injection. All rats survived 21 days after injection of monocrotaline and control-aptamer or RAGE-aptamer. Injection of monocrotaline with continuous subcutaneous delivery of control-aptamer resulted in higher right ventricular systolic pressure compared with controls. This increase was attenuated by continuous subcutaneous delivery of RAGE-aptamer. The proportion of small pulmonary arteries with full muscularization was greater in the monocrotaline and control-aptamer group than in the control group. Continuous subcutaneous delivery of RAGE-aptamer significantly reduced the percentage of small pulmonary arteries with full muscularization Conclusions: Continuous subcutaneous delivery of RAGE-aptamer suppresses development of monocrotaline-induced PAH in rats. Inhibition of RAGE ameliorates muscularization of 3 small pulmonary arteries. Treatment with RAGE-aptamer might be a new therapeutic option for PAH

Functional analysis of RRAS2 pathogenic variants with a Noonan-like phenotype

Introduction: RRAS2, a member of the R-Ras subfamily of Ras-like low-molecular-weight GTPases, is considered to regulate cell proliferation and differentiation via the RAS/MAPK signaling pathway. Seven RRAS2 pathogenic variants have been reported in patients with Noonan syndrome; however, few functional analyses have been conducted. Herein, we report two patients who presented with a Noonan-like phenotype with recurrent and novel RRAS2 pathogenic variants (p.Gly23Val and p.Gly24Glu, respectively) and the results of their functional analysis.Materials and methods: Wild-type (WT) and mutant RRAS2 genes were transiently expressed in Human Embryonic Kidney293 cells. Expression of RRAS2 and phosphorylation of ERK1/2 were confirmed by Western blotting, and the RAS signaling pathway activity was measured using a reporter assay system with the serum response element-luciferase construct. WT and p.Gly23Val RRAS2 were expressed in Drosophila eye using the glass multiple reporter-Gal4 driver. Mutant mRNA microinjection into zebrafish embryos was performed, and the embryo jaws were observed.Results: No obvious differences in the expression of proteins WT, p.Gly23Val, and p.Gly24Glu were observed. The luciferase reporter assay showed that the activity of p.Gly23Val was 2.45 ± 0.95-fold higher than WT, and p.Gly24Glu was 3.06 ± 1.35-fold higher than WT. For transgenic flies, the p.Gly23Val expression resulted in no adults flies emerging, indicating lethality. For mutant mRNA-injected zebrafish embryos, an oval shape and delayed jaw development were observed compared with WT mRNA-injected embryos. These indicated hyperactivity of the RAS signaling pathway.Discussion: Recurrent and novel RRAS2 variants that we reported showed increased in vitro or in vivo RAS signaling pathway activity because of gain-of-function RRAS2 variants. Clinical features are similar to those previously reported, suggesting that RRAS2 gain-of-function variants cause this disease in patients