Intraspecific genetic variation of a Fagus sylvatica population in a temperate forest derived from airborne imaging spectroscopy time series

1. The growing pace of environmental change has increased the need for large‐scale monitoring of biodiversity. Declining intraspecific genetic variation is likely a critical factor in biodiversity loss, but is especially difficult to monitor: assessments of genetic variation are commonly based on measuring allele pools, which requires sampling of individuals and extensive sample processing, limiting spatial coverage. Alternatively, imaging spectroscopy data from remote platforms may hold the potential to reveal genetic structure of populations. In this study, we investigated how differences detected in an airborne imaging spectroscopy time series correspond to genetic variation within a population of Fagus sylvatica under natural conditions.
2. We used multi‐annual APEX (Airborne Prism Experiment) imaging spectrometer data from a temperate forest located in the Swiss midlands (Laegern, 47°28'N, 8°21'E), along with microsatellite data from F. sylvatica individuals collected at the site. We identified variation in foliar reflectance independent of annual and seasonal changes which we hypothesize is more likely to correspond to stable genetic differences. We established a direct connection between the spectroscopy and genetics data by using partial least squares (PLS) regression to predict the probability of belonging to a genetic cluster from spectral data.
3. We achieved the best genetic structure prediction by using derivatives of reflectance and a subset of wavebands rather than full‐analyzed spectra. Our model indicates that spectral regions related to leaf water content, phenols, pigments, and wax composition contribute most to the ability of this approach to predict genetic structure of F. sylvatica population in natural conditions.
4. This study advances the use of airborne imaging spectroscopy to assess tree genetic diversity at canopy level under natural conditions, which could overcome current spatiotemporal limitations on monitoring, understanding, and preventing genetic biodiversity loss imposed by requirements for extensive in situ sampling.

     

The cytomegalovirus enhancer: a pan-active control element in transgenic mice.

In an effort to identify widely active positive regulatory elements, we have examined the action of the cytomegalovirus enhancer-promoter in transgenic mice. These elements activated expression in 24 of 28 tissues tested. The greatest expression was observed in the heart, kidney, brain, and testis. Maximum expression further localized to specific cells within the heart and kidney.     

The effect of 1,25-dihydroxyvitamin D3 on hematopoiesis in long-term human bone marrow cultures

The modulatory effect of 1,25-dihydroxyvitamin D3 (vit D) on the growth of myeloid progenitors and on the composition of the stromal layer in human bone marrow long-term cultures was studied. Vit D (2 X 10(-8) M) caused an enhancement in myeloid progenitor cell (CFU-C) growth in the nonadherent and adherent layers during the entire 5-week incubation period. The vitamin did not alter the differentiation pattern of CFU-C (monocyte-macrophage progenitors CFU-M, granulocytic progenitors CFU-G, or monocyte-granulocyte progenitors CFU-GM). Vit D caused a marked increase in the percentage of lipid-containing cells in the adherent layer and an increase in the number of cells that specifically bound My4 monoclonal antibody (McAb), that reacted positively to fluoride-sensitive alpha-naphthyl acetate esterase, and that phagocytosed Candida albicans (CA). Concentrated supernatants harvested from control cultures showed significant levels of myeloid colony stimulating factor (CSF) activity. The addition of vit D to cultures for 5 weeks did not alter CSF levels. These results suggest that vit D may play a role in hematopoiesis by acting directly on the progenitor cells or via the stromal cell production of stimulatory factor(s).     

C-banding polymorphism and the analysis of nucleolar activity in Dasypyrum villosum (L.) Candargy,its added chromosomes to hexaploid wheat and the amphiploid Triticum dicoccum — D. villosum

Summary C-banding patterns and nucleolar activity were analyzed in Dasypyrum villosum, its added chromosomes to hexaploid wheat and the hexaploid amphiploid Triticum dicoccum-D. villosum. Two different populations of the allogamous species D. villosum (2n= 14, VV) from Greece and Italy were analyzed showing a similar polymorphism for C-banding pattern. Six of the seven addition lines were identified by their characteristic C-banding pattern. No polymorphism between both members of each added alien chromosome was found. Furthermore, nucleolar activity and competition were studied by using silver staining procedure. In D. villosum only one chromosome pair, A, was found to be responsible for organizing nucleoli. The results obtained in the amphiploid and in the addition lines demonstrate that nucleolar activity is restricted to SAT-chromosomes 1B and 6B of wheat, while those of D. villosum remain inactive.     

Transfer of the 1BL/1RS wheat-rye-translocation from hexaploid bread wheat to tetraploid durum wheat

Summary The present study describes a cytological stable alien chromosome translocation in tetraploid durum wheat. By crossing the hexaploid 1BL/1RS wheat-rye translocation line Veery to the tetraploid durum wheat cultivar Cando it was possible to select a 28 chromosomic strain homozygous for the 1BL/1RS translocation. The disease resistance potential of the short arm of rye chromosome 1R, which has been widely introduced in many hexaploid bread wheat cultivars could be now also used for the improvement of durum wheat.     

The anatomy of the circumgenital scent gland of Saguinus fuscicollis (Callitrichidae, Primates)

In the adult male Saguinus fuscicollis , the scrotal skin and the area above the root of the penis are raised in a sharply defined cushion, which extends cranially into a rectangular suprapubic pad. The circumgenital area of the adult female resembles that of the male, except that the suprapubic pad is relatively and absolutely larger. A complex glandular organ, composed of holocrine and apocrine glands, is located beneath the epidermis of the circumgenital skin. In males, specialized holocrine glands associated with hair follicles predominate. They form a layer, 2-3 mm deep beneath the epidermis. These holocrine glands have a complex alveolar structure and possess numerously branched excretory ducts. Each group of glands empties into a common duct which enters the hair follicle. In males, the apocrine glands are located predominantly at the periphery of the glandular pad and between the scrotal and perineal areas. The excretory ducts of most apocrine glands empty on to the skin surface in close spatial association with hair follicles. However, independent openings were also observed. In females, the specialized holocrine glands resemble those of males but are more frequently interspersed with apocrine glands. The apocrine glands are larger and much more numerous than in males, especially in the region of the labia majora. Gonadectomy of an adult male and female resulted in a reduction in the size of the holocrine glands but had much less effect on the apocrine glands of the scent organ. In addition, the sexual dimorphism in gland histology was retained years after castration.