Biomedical subjects

Z Pancer

Publications and source records attributed to Z Pancer.

24 records · Page 2Linked to original sources

PubMed1995

Cloning of a urochordate cDNA featuring mammalian short consensus repeats (SCR) of complement-control protein superfamily.

Mammalian tumor necrosis factor (TNF)-alpha degenerate polymerase chain reaction (PCR) primers were used to amplify a probe from Botryllus schlosseri (colonial ascidian) allogeneic rejection-cDNA library. A PCR product (269 bp) was cloned and sequenced encoding an open reading frame (ORF) of 89 amino acids (aa). This clone, which revealed no similarity to TNF-alpha, but a substantial similarity to mammalian proteins featuring short consensus repeats (SCRs) of the complement control superfamily, was used to probe the rejection-cDNA library. Two partial cDNA clones were isolated and sequenced (Bs.1, 846 bp; Bs.2, 712 bp). The longest ORF in clone Bs.1 (which lacks the 5' end of the cDNA) predicts a protein of 251 aa, which differs from Bs.2 at six nucleotides and four aa. We compare the aa similarity (up to 50.5%) of Bs.1 with the SCR-region of mammalian complement factor H, apolipoprotein H, selectins, and complement receptors type 1 and type 2. A somatomedin B-like domain at the C-terminus of Bs.1 deduced protein was also recorded. We propose that this mosaic and polymorphic botryllid sequence, featuring mammalian-like SCRs, might be an ancestral molecule in the evolution of the chordate's complement-control protein superfamily.

Amino Acid Sequence↗

PubMed1994

Direct typing of polymorphic microsatellites in the colonial tunicate Botryllus schlosseri (ASCIDIACEA).

Five microsatellite loci of the marine protochordate Botryllus schlosseri were cloned: four of uninterrupted (AG)n repeats and one of both (AG)n and (TG)n repeats. By means of an innovative procedure small colony fragments were minimally treated to serve as templates for PCR with microsatellite-specific primers. Four of the loci were polymorphic: 7-8 discrete alleles were scored in nine colonies, heterozygosity ranging between 44-80%. At locus number 811 spacing of the alleles and gel-resolution were highest, therefore, ten additional colonies were typed and in total nine alleles were scored with maximal allelic interval of 120 base pair and 53% heterozygous colonies. The high levels of microsatellite-polymorphism provide a new tool as individual markers for studies on aspects of the botryllid polymorphic allorecognition system.

Animals↗

PubMed1994

Molecular cloning and localization of a novel serine protease from the colonial tunicate Botryllus schlosseri.

A cDNA encoding a putative serine protease was isolated and characterized from Botryllus schlosseri, a colonial protochordate. The open-reading frame of the 846 bp cDNA is 744-nt long. The deduced aa sequence predicts a protein of 26,134 D, with the signature of chymotrypsin. The mRNA of the protease is expressed only in the zooids as a single 0.9-kb transcript. No transcript was found in the tunic matrix (test). Surprisingly, a 3.7-fold higher enzyme activity was found in the test, compared with the zooids. We propose that this serine protease may have a role as a biologically active compound in the defense mechanisms against epibionts or as part of the effector mechanisms expressed in allogeneic and xenogeneic interactions.

Amino Acid Sequence↗

PubMed1993

cDNA cloning of a putative protochordate FK506-binding protein.

A tunicate (Botryllus schlossert) cDNA library was screened with a microsatellite probe. Five positive clones were sequenced, each with a 5' truncated microsatellite. One (Bs.6) revealed striking similarity to FK506 and rapamycin-binding proteins (FKBPs). Clone Bs.6 is 500 base pairs long and encodes for a putative protein of 134 amino acids. The predicted protein features the two FKBP-type peptidyl-prolyl cis-trans isomerase (PPIase) signatures and an endoplasmic reticulum retention signal. This protochordate protein is substantially similar to 12-13 kDa FKBPs, most remarkably to one of the receptors that had been proposed to mediate the immunosuppressive actions of FK506, the human FKBP-13 (62% amino acid identity and 74% similarity).

Amino Acid Sequence↗

PubMed1991

Implantation of chicken embryonic tissue and cells into unfertilised eggs.

1. Chick embryo cells and halved embryos were successfully implanted into unfertilised eggs. Yolks containing implants were placed in recipient eggshells, covered by transparent vacuum-formed plastic cones and incubated for 72 h. 2. Dispersed cells were obtained from eggs expelled from the uterus or from eggs that had been laid. Implantation of these cells often resulted in aggregation and epithelial growth, in several cases with axial development. 3. Growth of implanted halved embryos of different ages was often observed, including one 10-somite embryo. Non-axial epithelia, sometimes with a central hole, a central fluid-filled cellular vesicle or a vesicle only, were also observed. 4. In another culture system, whole and halved embryos obtained from laid eggs were cultured on a vitelline membrane stretched across semi-solid egg albumen. During the 72 h incubation, axial development was observed only in whole embryos, while halved embryos grew either into epithelia containing fluid-filled cellular vesicles or into vesicles only. 5. It was found that daily drainage of the accumulating fluid from the embryo compartment encouraged axial development in halved embryos, and almost abolished vesicle formation. Holes were formed in half the embryos cultured on a vitelline membrane. 6. It appeared that physical and biological conditions could inflict serious malformations on the implants.

Animals↗

PubMed1989

Recovery of ova and their re-insertion into the hen's oviduct through a fistula.

1. The first loop of the domestic hen's magnum was fistulated. A cannula mounted with a collecting tube served to trap the passing ova about 2.5 h following ovulation. 2. Nine out of 10 fistulated hens resumed ovulation about 2 to 5 weeks following surgery. A total of 63 magnal ova were collected. 3. Five of the magnal ova were successfully returned to the oviduct through the fistula and resulted in 5 normal soft-shelled eggs. The success of ova reimplantation was affected by prolapse of the posterior part of the oviduct and the timing of ova return.

Animals↗