scholarly journals The origin of the triploid in Paragonimus westermani on the basis of variable regions in the mitochondrial DNA

2003 ◽  
Vol 77 (4) ◽  
pp. 279-285 ◽  
Author(s):  
T. Agatsuma ◽  
M. Iwagami ◽  
Y. Sato ◽  
J. Iwashita ◽  
S.J. Hong ◽  
...  

AbstractTriploid, parthenogenetic forms of the lungfluke, Paragonimus westermani, occur in Japan, Korea and China. The origin(s) of triploidy has been debated over the years. Sequences of two regions in the mitochondrial DNA, i.e. partial lrRNA (16S), and a portion of the non-coding region, were obtained from natural populations of P. westermani. All triploid individuals (Japan, Korea, China) and a single tetraploid individual (China) had identical sequences in the 16S region studied. Some sequence variation was observed among diploids, with those from Taiwan being distinct from the remainder. Both neighbour joining and parsimony trees using the 16S region placed diploid individuals from southwestern Japan close to the triploids and the tetraploid. The fragment amplified from the mitochondrial non-coding region showed dimorphism. One form (type A) consisted of 239 bp comprising two identical tracts of 70 bp separated by a tract of 93 bp. The second form (Type B) consisted of only a single 70 bp tract. All diploid individuals from Taiwan, China and Korea possessed type A, while those from Japan were polymorphic; individuals from Oita and Hyogo had type B, those from Chiba had type A, but both types were found in Mie. On the other hand, all of the triploid individuals and two tetraploid individuals possessed type B. Both the form present in the non-coding region and the 16S sequence suggest an affinity between a south-eastern group of diploid populations in Japan and the triploid form. A possible mechanism responsible for the origin of the triploid is discussed.


1972 ◽  
Vol 127 (5) ◽  
pp. 775-780 ◽  
Author(s):  
R. L. Wiseman ◽  
J. E. Fothergill ◽  
L. A. Fothergill

Two forms of hen ovalbumin that exist as genetic variants were compared by physical and immunochemical techniques. The two ovalbumins could be distinguished by electrophoretic mobility and by antisera that had been pretreated with heterologous antigen. Peptide `maps' of chymotrypsin digests of the two ovalbumins revealed that three of the peptides were different. These were isolated and analysed. One form of ovalbumin (type B) contains the sequence: -Ser-Ser-Ala-Asp-Leu-Ser-Gly-Ile-Ala-Glu-Ser(Ser,Leu)- whereas the other form (type A) contains an asparagine residue in place of the aspartic acid residue. The -Asn-Leu-Ser- sequence of type A is not glycosylated. Chymotrypsin readily cleaved the leucine–serine bond in the asparagine-containing peptide, but not in the aspartic acid-containing variant.



Genome ◽  
1992 ◽  
Vol 35 (3) ◽  
pp. 510-515 ◽  
Author(s):  
W. K. Kim ◽  
R. L. Innes ◽  
E. R. Kerber

Total genomic DNA of 27 accessions representing six Aegilops species was restricted with BamHI, EcoRI, and BamHI plus EcoRI, and the restriction fragments were probed with the ribosomal clones pMF2 containing the ribosomal RNA coding regions. The rDNA repeat lengths varied between 9.0 and 10.8 kb. Intraspecific variation among the 10 accessions of Ae. squarrosa var. strangulata ranged from 9.0 to 9.6 kb, suggesting a diversity of genotypes within as well as between species. These variations were not related to their geographical distributions. Each of 24 accessions had two BamHI sites in the coding region (type A), while three accessions of Ae. squarrosa var. strangulata had four BamHI sites (type B, two sites in the intergenic region). Results for these three accessions of Ae. squarrosa var. strangulata suggest genotypic diversity in this species. In BamHI restriction of each accession, a third DNA fragment, ranging between 9.0 and 10.8 kb in type A and 6.0 kb in type B, resulted from lack of digestion at the 26S BamHI site. In double digestion, all rDNA repeat units were restricted by EcoRI, yielding 3.9-, 0.9-, and 4.8-kb fragments, the last of which arose from the lack of digestion at the 26S BamHI site, estimated to occur in 5–20% of the repeat units, depending on the accession.Key words: Triticum tauschii, RFLP, diversity.



Genetics ◽  
1991 ◽  
Vol 129 (1) ◽  
pp. 103-117
Author(s):  
L R Hale ◽  
R S Singh

Abstract Preliminary studies with restriction fragment length polymorphisms of mitochondrial DNA (mtDNA) in natural populations of Drosophila melanogaster revealed considerable variation in terms of nucleotide sequence and overall size. In this report we present data from more isofemale lines and more restriction enzymes, and explore the utility of the data in inferring a colonization history of this species. Size variation in the noncoding A + T-rich region is particularly plentiful, with size variants occurring in all restriction site haplotypes in all populations. We report here classes of small-scale mobility polymorphisms (apparent range of 20 bp) in specific restriction fragments in the coding region. The variation in one such fragment appears to be generated even more rapidly than in the noncoding region. On the basis of the distribution of restriction site haplotypes, the species range can be divided into three major regions along longitudinal lines: Euro-African populations are the most diverse and are taken to be oldest; Far East populations have a complex distribution of haplotypes; Western Hemisphere populations are the least diverse and are interpreted to be the youngest. The history inferred from mtDNA alone is remarkably similar to one based on several nuclear markers. The mtDNA haplotype distribution is also very different from that of allozymes in these same populations. We interpret this as further evidence that natural selection is still the most parsimonious explanation for the parallel latitudinal allozyme clines in this species.



Author(s):  
S. Fujinaga ◽  
K. Maruyama ◽  
C.W. Williams ◽  
K. Sekhri ◽  
L. Dmochowski

Yumoto and Dmochowski (Cancer Res.27, 2098 (1967)) reported the presence of mature and immature type C leukemia virus particles in leukemic organs and tissues such as lymph nodes, spleen, thymus, liver, and kidneys of SJL/J strain mice with Hodgki's-like disease or reticulum cell neoplasm (type B). In an attempt to ascertain the possibility that this neoplasia may be of viral origin, experiments with induction and transmission of this neoplasm were carried out using cell-free extracts of leukemic organs from an SJL/J strain mouse with spontaneous disease.It has been possible to induce the disease in low-leukemia BALB/c and C3HZB strain mice and serially transfer the neoplasia by cell-free extracts of leukemic organs of these mice. Histological examination revealed the neoplasia to be of either reticulum cell-type A or type B. Serial transfer is now in its fifth passage. In addition leukemic spleen from another SJL/J strain mouse with spontaneous reticulum cell neoplasm (type A) was set up in tissue culture and is now in its 141st serial passage in vitro. Preliminary results indicate that cell-free material of 39th tissue culture passage can reproduce neoplasia in BALB/c mice.



1992 ◽  
Vol 68 (03) ◽  
pp. 297-300 ◽  
Author(s):  
Monica Galli ◽  
Paul Comfurius ◽  
Tiziano Barbui ◽  
Robert F A Zwaal ◽  
Edouard M Bevers

SummaryPlasmas of 16 patients positive for both IgG anticardiolipin (aCL) antibodies and lupus anticoagulant (LA) antibodies were subjected to adsorption with liposomes containing cardiolipin. In 5 of these plasmas both the anticardiolipin and the anticoagulant activities were co-sedimented with the liposomes in a dose-dependent manner, whereas in the remaining cases only the anticardiolipin activity could be removed by the liposomes, leaving the anticoagulant activity (LA) in the supernatant plasma. aCL antibodies purified from the first 5 plasmas were defined as aCL-type A, while the term aCL-type B was used for antibodies in the other 11 plasmas, from which 2 were selected for this study.Prolongation of the dRVVT was produced by affinity-purified aCL-type A antibodies in plasma of human as well as animal (bovine, rat and goat) origin. aCL-type B antibodies were found to be devoid of anticoagulant activity, while the corresponding supernatants containing LA IgG produced prolongation of the dRVVT only in human plasma.These anticoagulant activities of aCL-type A and of LA IgG's were subsequently evaluated in human plasma depleted of β2-glycoprotein I (β2-GPI), a protein which was previously shown to be essential in the binding of aCL antibodies to anionic phospholipids. Prolongation of the dRVVT by aCL-type A antibodies was abolished using β2-GPI deficient plasma, but could be restored upon addition of β2-GPI. In contrast, LA IgG caused prolongation of the dRVVT irrespective of the presence or absence of β2-GPI.Since β2-GPI binds to negatively-charged phospholipids and impedes the conversion of prothrombin by the factor Xa/Va enzyme complex (Nimpf et al., Biochim Biophys Acta 1986; 884: 142–9), comparison was made of the effect of aCL-type A and aCL-type B antibodies on the rate of thrombin formation in the presence and absence of β2-GPI. This was measured in a system containing highly purified coagulation factors Xa, Va and prothrombin and lipid vesicles composed of 20 mole% phosphatidylserine and 80 mole% phosphatidylcholine. No inhibition on the rate of thrombin formation was observed with both types of aCL antibodies when either β2-GPI or the lipid vesicles were omitted. Addition of β2-GPI to the prothrombinase assay in the presence of lipid vesicles causes a time-dependent inhibition which was not affected by the presence of aCL-type B or non-specific IgG. In contrast, the presence of aCL-type A antibodies dramatically increased the anticoagulant effect of β2-GPI. These data indicate that the anticoagulant activity of aCL-type A antibodies in plasma is mediated by β2-GPI.



2013 ◽  
Vol 1 (1) ◽  
pp. 10
Author(s):  
Noar Muda Satyawan ◽  
Shelly Tutupoho ◽  
Yusli Wardiatno ◽  
Makoto Tsuchiya

Erosion rate on corals due to activities of other biota is called bioerosion. The rock-boring urchin, Echinometra mathaei, when it is abundant, plays a significant role in benthic ecosystems, including biological processes like coral erosion. During feeding, E. mathaei erodes calcium carbonate besides grazing on algae living on coral, so it plays an important role in both organic and inorganic carbons in coral reefs. The urchin E. mathaei actively feeds during the night time (nocturnal grazer). Although in Okinawa four types (A-D) of the urchin exist, the research only focused on the types A and B. Type A of E. mathaei produced 0.44951 g feces per day on average while type B produced 0.38030 g feces per day. CaCO3 analysis in feces and gut contents showed bioerosion rate of E. mathaei type A was 0.64492 g/individu/day, and 0.54436 g/individu/day in type B. There were no significant differences in bioerosion impact of E. mathaei type A and B© Laju erosi pada karang yang disebabkan oleh biota, dikenal dengan bioerosi. Bulu babi jenis Echinometra mathaei, ketika melimpah, menjadi sangat berpengaruh terhadap ekosistem bentik termasuk proses biologi seperti erosi karang. Selama aktivitas makan, E. mathaei menggerus kalsium karbonat dalam proporsi yang besar di samping alga yang tumbuh menempel pada karang sehingga memiliki peran penting dalam siklus karbon organik dan anorganik di ekosistem terumbu karang. Bulu babi E. mathaei aktif mencari makan pada malam hari (nocturnal grazer). Meskipun di Okinanawa ada 4 tipe (A-D), pada eksperimen kali ini memfokuskan pada tipe A dan B saja. Tipe A E. mathaei rata-rata memproduksi 0,44951 g feses/hari dan tipe B memproduksi 0,38030 g feses/hari. Berdasarkan analisis CaCO3 yang dilakukan pada feses dan isi lambung, laju bioerosi yang disebabkan oleh E. mathaei tipe A sebesar 0,64492 g/individu/hari sedangkan tipe B sebesar 0,54436 g/individu/hari. Tidak terdapat perbedaan dampak bioerosi yang signifikan antara E. mathaei tipe A dan B©



Author(s):  
Hiroshi Yamagishi ◽  
Megumi Jikuya ◽  
Kanako Okushiro ◽  
Ayako Hashimoto ◽  
Asumi Fukunaga ◽  
...  

AbstractCytoplasmic male sterility (CMS) observed in many plants leads defect in the production of functional pollen, while the expression of CMS is suppressed by a fertility restorer gene in the nuclear genome. Ogura CMS of radish is induced by a mitochondrial orf138, and a fertility restorer gene, Rfo, encodes a P-type PPR protein, ORF687, acting at the translational level. But, the exact function of ORF687 is still unclear. We found a Japanese variety showing male sterility even in the presence of Rfo. We examined the pollen fertility, Rfo expression, and orf138 mRNA in progenies of this variety. The progeny with Type H orf138 and Rfo showed male sterility when their orf138 mRNA was unprocessed within the coding region. By contrast, all progeny with Type A orf138 were fertile though orf138 mRNA remained unprocessed in the coding region, demonstrating that ORF687 functions on Type A but not on Type H. In silico analysis suggested a specific binding site of ORF687 in the coding region, not the 5′ untranslated region estimated previously, of Type A. A single nucleotide substitution in the putative binding site diminishes affinity of ORF687 in Type H and is most likely the cause of the ineffectiveness of ORF687. Furthermore, fertility restoration by RNA processing at a novel site in some progeny plants indicated a new and the third fertility restorer gene, Rfs, for orf138. This study clarified that direct ORF687 binding to the coding region of orf138 is essential for fertility restoration by Rfo.



2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii41-ii41
Author(s):  
Junjie Zhen ◽  
Lei Wen ◽  
Shaoqun Li ◽  
Mingyao Lai ◽  
Changguo Shan ◽  
...  

Abstract BACKGROUND According to EANO-ESMO clinical practice guidelines, the MRI findings of LM are divided into 4 types, namely linear enhancement (type A), nodular enhancement (type B), linear combined with nodular enhancement (type C), and sign of hydrocephalus (type D). METHODS The MRI features of brain and spinal cord in patients diagnosed with NSCLC-LM in Guangdong Sanjiu Brain Hospital from 2010 until 2019 were investigated, and then were classified into 4 types. The imaging features were analyzed. RESULTS A total of 80 patients were enrolled in the study. The median age of the patients was 53.5 years old, and the median time from the initial diagnosis to the confirmed diagnosis of LM was 11.6 months. The results of enhanced MRI examination of the brain in 79 cases showed that the number of cases with enhancements of type A, B, C and D were 50 (63.3%), 0, 26 (32.9%) and 3 (3.8%), respectively, and that LM with metastases to the brain parenchyma was found in 42 cases (53.2%). The results of enhanced MRI examination of spinal cord in 59 cases showed that there were only enhancements of type A and C in 40 cases (67.8%) and 3 cases (5.0%), and no enhancement sign in the other 16 cases (27.2%). CONCLUSION MRI examination of brain and spinal cord will improve the detection rate of LM. The MRI features of NSCLC-LM in real world are mainly characterized by the linear enhancements of brain and spinal cord, followed by linear combined with nodular enhancement. The enhancements of type B and type D are rare in clinic. Almost half of the patients have LM and metastases to the brain parenchyma. Therefore, the differentiation of tumor metastases is needed to be paid attention to for the early diagnosis and the formulation of reasonable treatment plans.



BMC Genomics ◽  
2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Hüseyin Can ◽  
Sedef Erkunt Alak ◽  
Ahmet Efe Köseoğlu ◽  
Umut Şahar ◽  
Berna Bostanbaş ◽  
...  

Abstract Background Cytidine monophospho-n-acetylneuraminic acid hydroxylase (CMAH) gene associated with blood groups in cats encodes CMAH enzyme that converts Neu5Ac to Neu5Gc. Although variations in CMAH gene of pedigree cats have been revealed, the presence/lack of them in non-pedigree stray cats is unknown. Therefore, the present study aimed to investigate the variations in CMAH gene and the quantity of Neu5Ac and Neu5Gc on erythrocytes of non-pedigree stray cats (n:12) living in İzmir, Turkey. Also, the frequency of blood types was determined in 76 stray cats including 12 cats that were used for CMAH and Neu5A/Neu5Gc analysis. Results In total, 14 SNPs were detected in 5’UTR as well as in exon 2, 4, 9, 10, 11 and 12 of CMAH gene. Among these SNPs, -495 C > T in 5’UTR was detected for the first time as heterozygous in type A and AB cats, and homozygous and heterozygous in type B cats. The remaining 13 that have been detected in previous studies were also found as homozygous or heterozygous. Both Neu5Gc and Neu5Ac were detected in type A and AB cats. In type B cats, only Neu5Ac was detected. Among two type AB cats, the level of Neu5Ac was found higher in cat carrying heterozygous form (T/C) of 1392T > C. The prevalence of type B cats (67.1 %) was higher than others. Conclusions The presence of a new SNP as well as previous SNPs indicates that more variations can be found in stray cats with a more comprehensive study in the future. Also, the high prevalence of type B cats demonstrates the possible risk of neonatal isoerythrolysis among stray cats living in İzmir, Turkey.



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