scholarly journals Free-Living Tube Worm Endosymbionts Found at Deep-Sea Vents

2008 ◽  
Vol 74 (12) ◽  
pp. 3895-3898 ◽  
Author(s):  
Tara L. Harmer ◽  
Randi D. Rotjan ◽  
Andrea D. Nussbaumer ◽  
Monika Bright ◽  
Andrew W. Ng ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Sequence Analysis ◽  
Dna Sequence ◽  
Deep Sea ◽  
Pcr Amplification ◽  
Free Living ◽  
Endosymbiotic Bacteria ◽  
Tube Worms ◽  
Symbiont Acquisition

ABSTRACT Recent evidence suggests that deep-sea vestimentiferan tube worms acquire their endosymbiotic bacteria from the environment each generation; thus, free-living symbionts should exist. Here, free-living tube worm symbiont phylotypes were detected in vent seawater and in biofilms at multiple deep-sea vent habitats by PCR amplification, DNA sequence analysis, and fluorescence in situ hybridization. These findings support environmental transmission as a means of symbiont acquisition for deep-sea tube worms.

Isolation and chromosomal localization of new MITE-like sequences from Secale

Biologia ◽  
2012 ◽  
Vol 67 (1) ◽  
Author(s):  
Lijun Hu ◽  
Zixian Zeng ◽  
Cheng Liu ◽  
Guangrong Li ◽  
Zujun Yang
Keyword(s):  
In Situ Hybridization ◽  
Sequence Analysis ◽  
Molecular Marker ◽  
Dna Sequence ◽  
Chromosomal Localization ◽  
Repetitive Element ◽  
Addition Lines ◽  
Secale Africanum ◽  
Species Specific

AbstractA species-specific DNA sequence (marker) that can detect the presence of Secale cereale chromatin in common wheat background was developed by using wheat microsatellite primer Xgwm614. One rye-specific DNA amplified fragment of 416bp (pSa614416) was obtained from Secale africanum and a wheat — S. africanum amphiploid. The primer Xgwm614 also gave rise to specific bands in all Chinese Spring-Imperial rye addition lines 1R to 7R. Sequence analysis revealed that pSa614416 was strongly homologous to a miniature inverted transposable element (MITE) stowaway-like element. Results of fluorescence in situ hybridization showed that the signal of pSa614416 was distributed along all S. cereale. cv Jingzhou chromosomes, but the signal strengths were unbalanced on the seven rye genome chromosomes. This repetitive element may be useful as a molecular marker for the introgression of rye germplasm into the wheat genome.

DNA sequence mapping in interphase and metaphase chromosomes by fluorescence in situ hybridization

1992 ◽  
Vol 50 (1) ◽  
pp. 496-497
Author(s):  
Barbara Trask ◽  
Susan Allen ◽  
Anne Bergmann ◽  
Mari Christensen ◽  
Anne Fertitta ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Dna Sequence ◽  
Dna Sequences ◽  
Dual Band ◽  
Nick Translation ◽  
Metaphase Chromosomes ◽  
Band Pass ◽  
Texas Red ◽  
Fluorescent Spot

Using fluorescence in situ hybridization (FISH), the positions of DNA sequences can be discretely marked with a fluorescent spot. The efficiency of marking DNA sequences of the size cloned in cosmids is 90-95%, and the fluorescent spots produced after FISH are ≈0.3 μm in diameter. Sites of two sequences can be distinguished using two-color FISH. Different reporter molecules, such as biotin or digoxigenin, are incorporated into DNA sequence probes by nick translation. These reporter molecules are labeled after hybridization with different fluorochromes, e.g., FITC and Texas Red. The development of dual band pass filters (Chromatechnology) allows these fluorochromes to be photographed simultaneously without registration shift.

The use of double fluorescence in situ hybridization to physically map the positions of 5S rDNA genes in relation to the chromosomal location of 18S–5.8S–26S rDNA and a C genome specific DNA sequence in the genus Avena

Genome ◽  
1996 ◽  
Vol 39 (3) ◽  
pp. 535-542 ◽  
Author(s):  
Concha Linares ◽  
Juan González ◽  
Esther Ferrer ◽  
Araceli Fominaya
Keyword(s):  
In Situ Hybridization ◽  
Dna Sequence ◽  
Diploid Species ◽  
5S Rdna ◽  
Rdna Genes ◽  
26S Rdna ◽  
A Genome ◽  
Rdna Loci ◽  
C Genome

A physical map of the locations of the 5S rDNA genes and their relative positions with respect to 18S–5.8S–26S rDNA genes and a C genome specific repetitive DNA sequence was produced for the chromosomes of diploid, tetraploid, and hexaploid oat species using in situ hybridization. The A genome diploid species showed two pairs of rDNA loci and two pairs of 5S loci located on both arms of one pair of satellited chromosomes. The C genome diploid species showed two major pairs and one minor pair of rDNA loci. One pair of subtelocentric chromosomes carried rDNA and 5S loci physically separated on the long arm. The tetraploid species (AACC genomes) arising from these diploid ancestors showed two pairs of rDNA loci and three pairs of 5S loci. Two pairs of rDNA loci and 2 pairs of 5S loci were arranged as in the A genome diploid species. The third pair of 5S loci was located on one pair of A–C translocated chromosomes using simultaneous in situ hybridization with 5S rDNA genes and a C genome specific repetitive DNA sequence. The hexaploid species (AACCDD genomes) showed three pairs of rDNA loci and six pairs of 5S loci. One pair of 5S loci was located on each of two pairs of C–A/D translocated chromosomes. Comparative studies of the physical arrangement of rDNA and 5S loci in polyploid oats and the putative A and C genome progenitor species suggests that A genome diploid species could be the donor of both A and D genomes of polyploid oats. Key words : oats, 5S rDNA genes, 18S–5.8S–26S rDNA genes, C genome specific repetitive DNA sequence, in situ hybridization, genome evolution.

scholarly journals Metatranscriptomics by In Situ RNA Stabilization Directly and Comprehensively Revealed Episymbiotic Microbial Communities of Deep-Sea Squat Lobsters

mSystems ◽  
2020 ◽  
Vol 5 (5) ◽  
Author(s):  
Kaori Motoki ◽  
Tomo-o Watsuji ◽  
Yoshihiro Takaki ◽  
Ken Takai ◽  
Wataru Iwasaki
Keyword(s):  
Deep Sea ◽  
Expression Profiles ◽  
Rna Degradation ◽  
Rna Expression ◽  
Free Living ◽  
Content Type ◽  
Living State ◽  
Rna Stabilization ◽  
Squat Lobsters

ABSTRACT Shinkaia crosnieri is an invertebrate that inhabits an area around deep-sea hydrothermal vents in the Okinawa Trough in Japan by harboring episymbiotic microbes as the primary nutrition. To reveal physiology and phylogenetic composition of the active episymbiotic populations, metatranscriptomics is expected to be a powerful approach. However, this has been hindered by substantial perturbation (e.g., RNA degradation) during time-consuming retrieval from the deep sea. Here, we conducted direct metatranscriptomic analysis of S. crosnieri episymbionts by applying in situ RNA stabilization equipment. As expected, we obtained RNA expression profiles that were substantially different from those obtained by conventional metatranscriptomics (i.e., stabilization after retrieval). The episymbiotic community members were dominated by three orders, namely, Thiotrichales, Methylococcales, and Campylobacterales, and the Campylobacterales members were mostly dominated by the Sulfurovum genus. At a finer phylogenetic scale, the episymbiotic communities on different host individuals shared many species, indicating that the episymbionts on each host individual are not descendants of a few founder cells but are horizontally exchanged. Furthermore, our analysis revealed the key metabolisms of the community: two carbon fixation pathways, a formaldehyde assimilation pathway, and utilization of five electron donors (sulfide, thiosulfate, sulfur, methane, and ammonia) and two electron accepters (oxygen and nitrate/nitrite). Importantly, it was suggested that Thiotrichales episymbionts can utilize intercellular sulfur globules even when sulfur compounds are not usable, possibly also in a detached and free-living state. IMPORTANCE Deep-sea hydrothermal vent ecosystems remain mysterious. To depict in detail the enigmatic life of chemosynthetic microbes, which are key primary producers in these ecosystems, metatranscriptomic analysis is expected to be a promising approach. However, this has been hindered by substantial perturbation (e.g., RNA degradation) during time-consuming retrieval from the deep sea. In this study, we conducted direct metatranscriptome analysis of microbial episymbionts of deep-sea squat lobsters (Shinkaia crosnieri) by applying in situ RNA stabilization equipment. Compared to conventional metatranscriptomics (i.e., RNA stabilization after retrieval), our method provided substantially different RNA expression profiles. Moreover, we discovered that S. crosnieri and its episymbiotic microbes constitute complex and resilient ecosystems, where closely related but various episymbionts are stably maintained by horizontal exchange and partly by their sulfur storage ability for survival even when sulfur compounds are not usable, likely also in a detached and free-living state.

scholarly journals Ontogenetic Pattern of Thyroid Hormone Receptor Expression in the Human Testis

2000 ◽  
Vol 85 (9) ◽  
pp. 3453-3457 ◽  
Author(s):  
Emmanuele A. Jannini ◽  
Anna Crescenzi ◽  
Nadia Rucci ◽  
Emiliano Screponi ◽  
Eleonora Carosa ◽  
...  
Keyword(s):  
In Situ Hybridization ◽  
Thyroid Hormone ◽  
Sertoli Cells ◽  
Pcr Amplification ◽  
Receptor Expression ◽  
Northern Analysis ◽  
Human Testis ◽  
Adult Testis ◽  
Maximal Expression

Abstract We studied the spatiotemporal distribution of thyroid hormone nuclear receptors (TRs) α1 and α2 and β messenger RNA (mRNA) levels in normal human testicular tissue during development and in adulthood. Nonpathological specimens from five aborted fetuses (17 and 23 weeks of gestation, three and two cases, respectively) and from four patients undergoing orchiectomy (18 months old and 38-, 42-, and 52-yr-old, respectively) were analyzed by Northern blot, semiquantitative RT-PCR amplification using DNA sequences or specifically designed primers for the TR isoforms, and in situ hybridization. By using PCR amplification, we found that TRα1 and TRα2 are both expressed at different levels in fetal and adult testis. At all ages TRα2 is found at higher levels. Northern analysis showed hybridization signals corresponding to the expression of TRα2 and TRα1 in a ratio that increased from 2.6 at 17 weeks of gestation to 12.0 in adulthood. In fact, the expression of TRα1 dramatically decreased throughout development, being faintly detectable in the adult testis. Expression of TRβ was not detected at any age studied. This finding was further confirmed by PCR, which did not amplify TRβ either in fetal or in adult testis mRNAs. In situ hybridization studies showed the absence of TRβ and that TRα1 and TRα2 colocalized in Sertoli cells of prepubertal testis, whereas germ and interstitial cells appeared devoid of TR mRNA signals. From these results it can be concluded that the human testis exclusively expresses TRα, which is localized in Sertoli cells, TRβ being always undetectable. Fetal and prepubertal ages represent the period of maximal expression of TRα1 and TRα2. Theα 2/α1 ratio rises dramatically after development. These results confirm a critical window for the action of thyroid hormone in human testis, in the period of maximal expression of T3 binding isoform TRα1, and may account for the macroorchidism without virilization occurring when hyposecretion of thyroid hormones occurs before puberty.

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