Molecular delineation of the Y-borne Sry gene in the Formosan pangolin (Manis pentadactyla pentadactyla) and its phylogenetic implications for Pholidota in extant mammals

The systematic status of Pholidota has been a matter of debate, particularly regarding the apparent inconsistency between morphological and molecular studies. The Sry gene, a master regulator of male sex determination in eutherian mammals, has not yet been used for phylogenetic analyses of extant mammals. The objective of the present study was to clone and characterize the complete gene (1300 base pairs; bp) and amino acid sequences (229 residues) of Sry from the Formosan pangolin (Manis pentadactyla pentadactyla), a member of Pholidota. The Sry amino acid identity between pangolin and other reported species ranged from 42.5% (mouse, Mus musculus) to 84.1% (European hare, Lepus europaeus). Sequence conservation was primarily in the high motility group (HMG) box (234 bp), whereas homology outside the HMG box was low. The cloned Sry was mapped to the pangolin Y chromosome by fluorescence in situ hybridization (FISH); this was confirmed to be the first Y-borne molecular marker identified in Pholidota. Based on Bayesian phylogenetic analysis for Sry HMG sequences from 36 representative taxa, including the Formosan pangolin, Pholidota was more closely related to Carnivora than to Xenarthra, consistent with the emerging molecular tree inferred from markers not located on the Y chromosome. In conclusion, this study characterized the gene structure of Sry of the Formosan pangolin and provided insights into the phylogenetic position of Pholidota.     

Foraging behaviour and ecology of the Cape pangolin (Manis temminckii) in north‐western Zimbabwe

An ethogram was developed for the foraging Cape pangolin in order to construct activity budgets. Behaviour was classified into seven categories and nine types of feeding sites were recorded. Activity budgets of animals foraging in different vegetation types are presented to illustrate the importance of vegetation on behaviour patterns and feeding site utilization. Availability of feeding sites may depend on the vegetation type with trees, shrubs and woody debris comprising most feeding sites. Seven prey species were recorded. One animal displayed strictly diurnal activity which suggests greater variability in activity patterns than previously thought.     

Information on the distribution of Formosan monkeys (Macaca cyclopis)

The distribution of Formosan monkeys in Taiwan has been researched by the Macaque Research Group of Japan since 1967. In 1982, the Macaque Research Group of Japan conducted a questionnaire survey. From our past surveys, the answers to the questionnaire, and the 1982 survey, we were able to list 75 habitats of Formosan monkeys. The monkey population is more concentrated in southeast Taiwan than in other areas. This biased pattern of distribution may be attributed to the effect of forest destruction and regional development, rather than to the hunting activities by man. The density of monkey groups was estimated to be at least 0.1 group/km². The range of the group of Formosan monkeys at Chihpen village, Taitung, was estimated to be about 2 km². The size of this group is comparable to the average group size of Japanese monkeys.     

Progesterone signals through membrane progesterone receptors (mPRs) in MDA-MB-468 and mPR-transfected MDA-MB-231 breast cancer cells which lack full-length and N-terminally truncated isoforms of the nuclear progesterone receptor

The functional characteristics of membrane progesterone receptors (mPRs) have been investigated using recombinant mPR proteins over-expressed in MDA-MB-231 breast cancer cells. Although these cells do not express the full-length progesterone receptor (PR), it is not known whether they express N-terminally truncated PR isoforms which could possibly account for some progesterone receptor functions attributed to mPRs. In the present study, the presence of N-terminally truncated PR isoforms was investigated in untransfected and mPR-transfected MDA-MB-231 cells, and in MDA-MB-468 breast cancer cells. PCR products were detected in PR-positive T47D Yb breast cancer cells using two sets of C-terminus PR primers, but not in untransfected and mPR-transfected MDA-MB-231 cells, nor in MDA-MB-468 cells. Western blot analysis using a C-terminal PR antibody, 2C11F1, showed the same distribution pattern for PR in these cell lines. Another C-terminal PR antibody, C-19, detected immunoreactive bands in all the cell lines, but also recognized α-actinin, indicating that the antibody is not specific for PR. High affinity progesterone receptor binding was identified on plasma membranes of MDA-MB-468 cells which was significantly decreased after treatment with siRNAs for mPRα and mPRβ. Plasma membranes of MDA-MB-468 cells showed very low binding affinity for the PR agonist, R5020, ≤1% that of progesterone, which is characteristic of mPRs. Progesterone treatment caused G protein activation and decreased production of cAMP in MDA-MB-468 cells, which is also characteristic of mPRs. The results indicate that the progestin receptor functions in these cell lines are mediated through mPRs and do not involve any N-terminally truncated PR isoforms.     

Observations on the Oman Shark,Iago omanensis (Triakidae), with emphasis on the morphological and cytological changes of the oviduct and yolk sac during gestation

The shark Iago omanensis (Triakidae, Selachia) is encountered in large populations in the Gulf of Aqaba, Red Sea, at depths of 150–1,500 m. It is a placental viviparous species, reproductive all year round and giving birth to four (occasionally five) young of 170- to 180-mm total length (TL). Its distribution and morphometrics, as well as histological and cytological changes in the oviducts, were studied. The ratio of weight of the female genital organs to body weight changes from 0.7% in nongravid females to 19.8% in the final stages of pregnancy. The ripe, liberated eggs, which are 11–12 mm long and 5 mm wide, pass through the nidamental gland and settle in the uterus. The embryo attains 9- to 11-mm TL and settles on a protruding ridge of the submucosa, covered with a microvillar endometrium. At this site of attachment, a placenta is formed and the participating uterine endometrium and wall of the yolk sac undergo profound histocytological changes, forming two parts of this organ. Three forms of food provisioning occur in the growing embryos: (1) lecithotrophic, based on yolk transported from the egg to the embryonic gut via the umbilical cord; (2) mixed food provision, during which, in addition to nourishment provided via the umbilicus, food is transported across the placenta through transfer from the female blood vascular system to the embryonic yolk sac via the trophic villi of the yolk sac; and (3) histotrophic, when all yolk reserves have been used and nutrition is provided from the so-called “milk” within the yolk sac, metabolized by the trophic structures of the sac and transported by blood vessels. Despite the gradual utilization of yolk, the yolk sac mass initially increases from 0.5–1.0 cc to 2.0–2.2 cc with the addition of primary and secondary trophic villi until, during the final stages of embryogenesis, it decreases again to 1.4–1.6 cc. Neonate juveniles are 35–40 times heavier than the original eggs. J. Morphol. 236:151–165, 1998. © 1998 Wiley-Liss, Inc.