Familial interactions of male rhesus monkeys in a semi-free-ranging troop

Although the central and stable position of female rhesus monkeys in semi-free-ranging bands has been observed and described, the position of the developing male in the social group is not as well delineated. The present study is an attempt to describe interactions of 18 males with members of their families. Quantitative observations were made on one band (E) of rhesus monkeys on Cayo Santiago. Incidences of behavior recorded were joining, grooming, and threatening. The resulting data were analyzed by comparing the behavior of the males studied toward members of their genealogy as well as unrelated members of the social group. Behavior of family and non-relatives toward the males was also revealed. Statistical analysis revealed that the male subjects engaged in more positive social interactions within the matrifocal family than with other members of the genealogy, and in turn, more such behavior was observed within the genealogy than with unrelated monkeys. Threatening behavior within the genealogies was infrequent. Age effects were noted in that family members directed more interactions toward younger males and as males matured, they groomed more but joined family members less frequently. These data suggest mechanisms of socialization within the genealogy that may be different from those employed within the unrelated social group.     

Molecular mechanisms of hormone controlled gene expression in the breast

In a meritorious effort H. de Rothschild compiled in 1899 all publications on mammary gland development and milk – a grand total of 8375 [1]. In the preface to this publication Duclaux states: ‘Such a discrepancy between the tremendous efforts and the paltriness of the results – hundreds of scientists and thousands of research years, just to create 200 or 300 pages of truth’. The number of papers added since then must be enormous. Rather than reviewing a vast literature, I will take the liberty and focus on research which, in my opinion, shaped our understanding of hormone controlled gene expression in the developing breast. This revised version was published online in August 2006 with corrections to the Cover Date.     

The maize autonomous element Activator (Ac) shows a minimal germinal excision frequency of 0.2%–0.5% in transgenic Arabidopsis thaliana plants

Summary The autonomous mobile element Activator from Zea mays was introduced into Arabidopsis thaliana via Agrobacterium-mediated gene transfer. The use of a chimaeric construct, where the Ac element is located in the leader of the neomycin phosphotransferase (NPT II) gene, enabled the excision of Ac to be monitored by assaying for the reconstitution of NPT II gene activity. Using this approach, the transpositional activity of AC was initially studied in primary transformants. About 50% of the regenerating Ac transformants showed evidence for excision of the element. Reintegration of Ac was confirmed by Southern blot analysis. Transposition events are transmitted to the F1 generation with a minimal frequency of 0.3%. In a few exceptional cases they are detected in a high proportion of the F1 generation. Seedlings from the F2 and F3 generations were assayed for the rate of germinal excisions by scoring for kanamycin resistance. The minimal frequency of germinal excision events amounts to 0.2%–0.5% and hence allows the use of the Ac element for gene tagging purposes in A. thaliana.     

A detailed study of the regulation and evolution of the two classes of patatin genes in Solanum tuberosum L.

The class-specific expression of patatin genes was investigated by analysing four new patatin genes. A class I patatin gene from cv. Berolina as well as a class I and two class II patatin genes from the monohaploid cultivar AM 80/5793 were isolated and partially sequenced. Sequence comparison indicates rearrangements as the major source for the generation of diversity between the different members of the classes. The expression of single genes was studied in potato plants transformed with chimaeric genes where the putative patatin promoters were fused to the GUS reporter gene. A detailed histochemical analysis reveals that both class I genes are expressed as the previously described class I patatin gene B33 from cv. Berolina [1], i.e. in the starch-containing cells of potato tubers and in sucrose-induced leaves. The class II gene pgT12 shows the same pattern as the previously described class II gene pgT2 [2], i.e. expression in root tips and in the vascular tissue of tubers, whereas no activity was detectable for pgT4. Thus the expression pattern of both classes of genes seems to be stable at least within or even between different cultivars.     

A new simple mouse model for the in vivo evaluation of cholecystokinin (CCK) antagonists: comparative potencies and durations of action of nonpeptide antagonists

A new simple mouse assay for the in vivo evaluation of CCK antagonists which is based upon visual determination of the gastric emptying of a charcoal meal is described. CCK-8 (24 micrograms/kg s.c.) but not various other peptide and nonpeptide agents effectively inhibited gastric emptying in this test system. The effect of CCK-8 was antagonized by established peripheral CCK antagonists but not representative agents of various other pharmacological classes. The rank order of potency of the CCK antagonists were: L-364,718 (ED50 = 0.01 mg/kg, i.v.; 0.04 mg/kg, p.o.) greater than Compound 16 (ED50 = 1.5 mg/kg, i.v.; 2.0 mg/kg p.o.) greater than asperlicin (ED50 = 14.8 mg/kg i.v.) greater than proglumide (ED50 = 184 mg/kg i.v.; 890 mg/kg, p.o.). Duration of action studies based upon ED50 values determined at various time intervals after oral administration showed that L-364,718 and proglumide are considerably longer acting than Compound 16. Asperlicin (ED50 greater than 300 mg/kg, p.o.) was ineffective as a CCK antagonist when administered orally. These data provide the first direct comparisons of the in vivo potencies of current CCK antagonists and demonstrate the utility of a new simple mouse assay for the in vivo characterization of peripheral CCK antagonists.     

Neuropeptide Y (NPY) binding sites in rat brain labeled with 125I-Bolton-Hunter NPY: comparative potencies of various polypeptides on brain NPY binding and biological responses in the rat vas deferens

The binding of biologically active 125I-Bolton-Hunter (BH)-NPY to rat brain membranes was saturable and reversible and regulated by inorganic cations and guanyl nucleotides consistent with other neurotransmitter receptor systems. The concentration of specific 125I-NPY binding differed in various brain regions, being highest in the hippocampus and lowest in the cerebellum. Scatchard analysis of 125I-NPY binding showed a single class of receptor sites with a Kd = 0.1 nM and Bmax of 3 pmole/g tissue in hippocampus. Peptide YY, porcine and human NPY inhibited the specific 125I-BH-NPY binding with IC50 values of 50-120 pM. In contrast, human NPY free acid and pancreatic polypeptides from human (HPP), rat (RPP) and avian (APP) sources were much weaker (IC50 greater than or equal to 300 nM). The rank order of potencies for NPY analogs and the inactivity of APP and HPP fragment (31-36) on brain binding appeared to correlate with their relative activities in inhibiting contractions of the field-stimulated rat vas deferens. However, PYY, HPP and RPP exhibited activity in the field-stimulated rat vas deferens indicative of a possible action upon sites distinct from the brain NPY binding site.