Vol.28-Issue 3 - 2004
Vol.28-Issue 3 - 2004
Tissue expression of platelet endothelial cell adhesion molecule-1
at pre and postnatal murine development
GRACIELA CRISTINA CALABRESE* AND ROSA WAINSTOK**.
* Cátedra de Biología Celular e Histología, Departamento de Ciencias Biológicas. Facultad de Farmacia y Bioquímica.
Universidad de Buenos Aires. Junin 954/6, 1113 Buenos Aires, Argentina.
** Departamento de Química Biológica. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires. Ciudad
Universitaria, Pabellón II, 4º Piso, Nuñez, 1428 Buenos Aires, Argentina.
Key words: Endothelial cells, PECAM-1, vasculogenesis, mouse organs.
ABSTRACT: Endothelial cells, at the cell-cell borders, express PECAM-1, and have been implicated in
vascular functions. The monoclonal antibody MEC 13.3 recognizes PECAM-1 molecule from mouse vessels
and allows to analyze the ontogeny of mouse endothelium. At the present, little is known about the molecular
basis of differentiation pathways of endothelial cells, that enables its morphological heterogeneity. The purpose
of this study was to analyze the pattern of PECAM-1 expression, employing monoclonal antibody MEC
13.3, in cellular suspensions obtained from different mouse organs at pre and postnatal stages.
Fluorescence activated cell sorter analysis showed a different profile of the glycoprotein expression in a cell
population with size and granularity selected by 1G11 endothelial cell line. The expression differs from
prenatal to postnatal developmental stages in a given organ, and among the organs studied.
Another cell population, with a size and granularity higher than 1G11 endothelial cell line, coexists in cellular
suspensions obtained from liver, gut and brain. These cells could be related to those detected by means of
immunoenzyme methods which showed a non-differentiated morphology.
The different PECAM-1 pattern expression could reflect potential organ-specific differentiation pathways
during development and according to organs environment.
The existence of another cell population with a size and granularity higher than 1G11 endothelial cell line
required a phenotypic characterization.
Differentiation and morphogenesis of Triatoma infestans (Klug 1834)
female gonads. I – Post embryonic development
CECILIA I. IBAÑEZ DE BARRETT, JUAN PABLO BOZZINI, AND MARTA MARIANO DE BOZZINI*
A.N.L.I.S. Dr. Carlos G. Malbrán. Avda. Velez Sarsfield 563, (1281) Buenos Aires, Argentina.
*Member of the Research Career. National Research Council, Argentina.
Key words: Ovary, Development, Hemiptera, Insect Nymph
ABSTRACT: The post-embryonic development of the female gonads in Triatoma infestans (Hemiptera, Heteroptera), insects of importance in health affairs as harbors and vectors of different tripanosomatidea flagellates, is presented in a complete follow-up since insect hatches from the egg up to the last molt in the fifth instar stage. The detailed description of the morphological changes which occur in each instar as well as careful measurements evaluating its size increase have been analyzed by stereomicroscopy, phase contrast, dark field, and oblique illumination, in order to optimize the observations as well the photographic register of gonad morphology and structure. The analysis was performed on gonad specimens obtained from broods no less than twenty (20) nymph bugs, reared at constant temperature and fed-up regularly. According to the results of our study we can assert that gonad differentiation takes place in early phases of the insect development. Such is the case that first instars nymph’s present absolutely and easily recognizably male and female gonads. From the third instar on beside the filament region, the three zones in each ovariole body is distinguished, a differentiation that is more noticeable during the fourth instar where a definite organization is present at the vitelarium. Such a clear cut zone development continues intensively during the fifth instar. Finally at the end of such fifth nymph stage and when the last molt toward adults is prepared, clear signs of ovariole maturation take place since oocytes in early vitelogenesis are found.
Abbreviations used in the illustrations: est: stroma; f: suspensor filament; ft: terminal filament; ov: oocytes; ovd: oviduct; ovl: ovariole;
pd: pedicel; tr: trachea (s); tro: tropharium; tz: transition zone; vt: vitelarium;
Microcutting culture and morpho-physiological changes during
acclimation in two Lycium chilense cytotypes
PABLO HORACIO MASEDA1, JORGE HUGO LEMCOFF1, MERCEDES MURÚA2, NORA FRAYSSINET3,
AND MARTA SUSANA
CARCELLER1†
1 IFEVA - Cátedra de Fisiología Vegetal (CONICET-FAUBA), Universidad de Buenos Aires. Av. San Martín 4453, C1417DSE,
Buenos Aires, Argentina.
2 Department of Agronomy, Purdue University, Lilly Hall 1150, West Lafayette, IN, 47907-1150,USA.
3 Cátedra de Genética (FAUBA), Universidad de Buenos Aires. Av. San Martín 4453, C1417DSE Buenos Aires, Argentina.
† Deceased.
Key words: Microcuttings, Lycium chilense, subcultures, endangered species.
ABSTRACT: Lycium chilense, a deciduous perennial shrub, is one of the endangered native species of Patagonia due to sheep overgrazing. Chances of recolonization by seeds are scarce due to the limited density of propagules in the soil and very specific requirements for germination. The objective was to develop an in vitro propagation protocol that would help to perform reestablishment of this species in degraded areas of the Patagonian steppe. Seeds came from two provenances with different somatic number due to differences in ploidy level. Defoliated microcuttings were planted in test tubes with different growing media and taken to a growth chamber. Rooting percentage did not differ between origins, but higher values were encountered for medium without hormones. Subcultures increased significantly rooting percentage and reduced time to rooting. The leaves from micropropagated plants were thinner, did not exhibit hairs, and had poorly developed palisade parenchyma and less epicuticular waxes. In vitro leaves had lower stomatal density and their stomata were less functional when compared to acclimated leaves. A repopulation program of Lycium chilense based on microcutting culture, specially using subcultures, is feasible.
Karyotype description of Pomacea patula catemacensis
(Caenogastropoda, Ampullariidae), with an assessment of the
taxonomic status of Pomacea patula
MARÍA ESTHER DIUPOTEX-CHONG1, NÉSTOR J. CAZZANIGA2, ALEJANDRA HERNÁNDEZ-SANTOYO3, AND JOSÉ MIGUEL
BETANCOURT-RULE4
1. Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México. Circuito Exterior, Ciudad
Universitaria, Coyoacán 04510. México, D.F.
2. Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur. San Juan 670, 8000 Bahía Blanca.
Argentina.
3. Universidad Autónoma Metropolitana Iztapalapa. Iztapalapa 09340. México, D.F.
4. Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, Coyoacán
04510. México, D.F.
Key words: apple snails, chromosomes, taxonomy, phylogeny, Mexico.
ABSTRACT: Mitotic chromosomes of the freshwater snail Pomacea patula catemacensis (Baker 1922) were analyzed on gill tissue of specimens from the type locality (Lake Catemaco, Mexico). The diploid number of chromosomes is 2n = 26, including nine metacentric and four submetacentric pairs; therefore, the fundamental number is FN = 52. No sex chromosomes could be identified. The same chromosome number and morphology were already reported for P. flagellata, i.e., the other species of the genus living in Mexico. The basic haploid number for family Ampullariidae was reported to be nÊ =Ê 14 in the literature; so, its reduction to nÊ =Ê 13 is probably an apomorphy of the Mexican Pomacea snails. Lanistes bolteni, from Egypt, also shows nÊ =Ê 13, but its karyotype is much more asymmetrical, and seems to have evolved independently from P. flagellata and P. patula catemacensis. The nominotypical subspecies, P. patula patula (Reeve 1856), is a poorly known taxon, whose original locality is unknown. A taxonomical account is presented here, and a Mexican origin postulated as the most parsimonious hypothesis.
RNA fingerprinting using RAP-PCR identifies an EBAF
homologue mRNA differentially expressed in rat oviduct
PABLO A. VALDECANTOS, MARTÍN E. ARGAÑARAZ, CARLOS M. ABATE, AND DORA C. MICELI
Instituto Superior de Investigaciones Biológicas. INSIBIO (CONICET, Universidad Nacional de Tucumán),
Chacabuco 461, (4000) S.M. de Tucumán, Argentina.
Key words: differential gene expression, oviduct, RNA fingerprint, cDNA
ABSTRACT: As a step towards the identification of genes preferentially expressed in the oviduct during early rat embryo development, we isolated a cDNA fragment (Pr14) by using RNA arbitrarily primed PCR (RAP-PCR), being its expression restricted to oviduct and uterus; its mRNA is mainly expressed in oviduct during late luteal phase and early pregnancy. This fragment is 100% identical to a rat DNA sequence (Accession No. NW_047400) downstream the terminal exon of a Rattus norvegicus gene (Locus Link Accession No. LOC289316) similar to ebaf (endometrial bleeding-associated factor), a novel member of the Transforming Growth Factor superfamily. Northern analyses showed that this sequence hybridizes with 2.9 kb and 4.1 kb mRNAs in early pregnant rat oviducts. However, only the 4.1 kb mRNA was detected in the oviduct of non-pregnant rats, showing an increase from proestrus to diestrus. The expression of this oviduct-uterus specific mRNA suggests that the products of this gene may play a role in the oviductal reproductive process. Abbreviations: bp, base pair(s); dNTP, deoxyribonucleoside triphosphate; ebaf, endometrial bleeding-associated factor; EST, expressed sequence tag; ORF, open reading frame; poly A, polyadenylation signal; RAPPCR, RNA arbitrarily primed PCR; TGF-beta, Transforming growth factor-beta; UTR, untranslated region.
Protein detection in spermatids and spermatozoa of the butterfly
Euptoieta hegesia (Lepidoptera)
KARINA MANCINI AND HEIDI DOLDER
Departamento de Biologia Celular, Instituto de Biologia, Universidade Estadual de Campinas, Campinas/SP, Brasil.
Key words: ultrastructure, protein, apyrene, eupyrene.
ABSTRACT: This study was undertaken to detect protein components in both sperm types of the butterfly Euptoieta hegesia. These spermatozoa possess complex extracellular structures for which the composition and functional significance are still unclear. In the apyrene sperm head, the proteic cap presented an external ring and an internal dense content; basic proteins were detected only in external portions. In the tail, the paracrystalline core of mitochondrial derivatives and the axoneme are rich in proteins. The extratesticular spermatozoa are covered by a proteic coat, which presented two distinct layers. In eupyrene spermatozoa, acrosome and nucleus were negatively stained, probably because of their high compaction. In the tail, there is no paracrystalline core and the axoneme presented a very specific reaction for basic proteins. The lacinate and reticular appendages are composed of cylindrical sub-units and presented a light reaction to E-PTA and a strong reaction to tannic acid. A complex proteic coat also covers the extratesticular spermatozoa. We found similarities between both extratesticular coats, indicating a possible common origin. Both spermatozoon types are rich in proteins, especially the eupyrene appendages and the extratesticular coats. We believe that both coats are related to the sperm maturation and capacitation processes.
Brief Note
Proacrosin-acrosin activity in capacitated and acrosome reacted
sperm from cryopreserved bovine semen
M. I. ROSATTI, M. T. BECONI AND M. CÓRDOBA
Area of Biochemistry, School of Veterinary Sciences, University of Buenos Aires, Argentina
Keywords: bovine sperm, proacrosin-acrosin, heparin, quercitin, progesterone
ABSTRACT: Acrosin activity is associated with normal fertility in human and bovine spermatozoa. The aim
of the study was to determine the variation of the enzyme activity in the proacrosin-acrosin system in capacitated
and acrosome reacted cryopreserved bovine sperm. Enzyme activity was assessed spectrophotometrically
using N-a-benzoyl-DL-arginine p-nitroanilide (BAPNA) as specific substrate for acrosin at pH 8. Capacitation
with heparin and quercitin failed to induce conversion of proacrosin to acrosin. An increase in
acrosin activity produced by the presence of progesterone, in a dose-dependent manner, was related with the
induction of true acrosome reaction. The total level of acrosin activity registered showed that 96% of acrosin
of capacitated sperm samples and control is present in the zymogen form. Moreover, progesterone is capable
of duplicating the level of active enzyme, indicating that enzyme activity changes are related to acrosome
reaction, suggesting that only a minor proportion of the total of proacrosin-acrosin system is required in the
exocytotic process on cryopreserved bovine sperm.