Revisiting the North-South genetic discontinuity in Central African tree populations: the case of the low-density tree species Baillonella toxisperma

In the present study the qualitative land suitability evaluation by parametric and analytic hierarchy process (AHP) approaches was investigated for two tree species including Norway maple and black locust in the Toroq watershed, a semiarid region, in the northeast of Iran. The values of land suitability indices by the parametric approach for Norway maple and black locust plantations ranged from 22.46 to 67.50 and 23.23 to 75.11 respectively, while by the AHP approach they varied between 35.91 and 84.58 for Norway maple and from 32.87 to 94.31 for black locust plantations. The suitability classes for both tree species by the parametric approach were classified into moderately suitable in the eastern part of the basin, and not suitable in the middle and western parts of the study area. According to the AHP approach the suitability classes varied from highly suitable in some parts in the east to moderately suitable in the middle, east and some parts in the west and not suitable in some parts in the north and southwest of the basin.

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A Cellular Receptor of Human Rhinovirus Type 2, the Very-Low-Density Lipoprotein Receptor, Binds to Two Neighboring Proteins of the Viral Capsid

Journal of Virology ◽

10.1128/jvi.77.15.8504-8511.2003 ◽

2003 ◽

Vol 77 (15) ◽

pp. 8504-8511 ◽

Cited By ~ 31

Author(s):

Emmanuelle Neumann ◽

Rosita Moser ◽

Luc Snyers ◽

Dieter Blaas ◽

Elizabeth A. Hewat

Keyword(s):

Low Density Lipoprotein ◽

Density Lipoprotein ◽

Very Low Density Lipoprotein ◽

Low Density ◽

Lipoprotein Receptor ◽

Low Density Lipoprotein Receptor ◽

The North ◽

Density Lipoprotein Receptor ◽

The Individual ◽

Viral Protein 1

ABSTRACT The very-low-density lipoprotein receptor (VLDL-R) is a receptor for the minor-group human rhinoviruses (HRVs). Only two of the eight binding repeats of the VLDL-R bind to HRV2, and their footprints describe an annulus on the dome at each fivefold axis. By studying the complex formed between a selection of soluble fragments of the VLDL-R and HRV2, we demonstrate that it is the second and third repeats that bind. We also show that artificial concatemers of the same repeat can bind to HRV2 with the same footprint as that for the native receptor. In a 16-Å-resolution cryoelectron microscopy map of HRV2 in complex with the VLDL-R, the individual repeats are defined. The third repeat is strongly bound to charged and polar residues of the HI and BC loops of viral protein 1 (VP1), while the second repeat is more weakly bound to the neighboring VP1. The footprint of the strongly bound third repeat extends down the north side of the canyon. Since the receptor molecule can bind to two adjacent copies of VP1, we suggest that the bound receptor “staples” the VP1s together and must be detached before release of the RNA can occur. When the receptor is bound to neighboring sites on HRV2, steric hindrance prevents binding of the second repeat.

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Latitudinal shift in the timing of flowering of tree species across tropical Africa: insights from field observations and herbarium collections

Journal of Tropical Ecology ◽

10.1017/s0266467420000103 ◽

2020 ◽

Vol 36 (4) ◽

pp. 159-173

Author(s):

Dakis-Yaoba Ouédraogo ◽

Olivier J. Hardy ◽

Jean-Louis Doucet ◽

Steven B. Janssens ◽

Jan J. Wieringa ◽

...

Keyword(s):

Tree Species ◽

Central Africa ◽

Flowering Phenology ◽

Graphical Analysis ◽

Dry Season ◽

Circular Statistics ◽

Significant Shift ◽

The North ◽

Herbarium Data ◽

Herbarium Collections

AbstractTemporal and spatial patterns in flowering phenology were assessed for eight tropical African tree species. Specifically, the frequency and seasonality of flowering at seven sites in central Africa were determined using field data, graphical analysis and circular statistics. Additionally, spatial variation in the timing of flowering across species range was investigated using herbarium data, analysing the relative influence of latitude, longitude and timing of the dry season with a Bayesian circular generalized linear model. Annual flowering was found for 20 out of the 25 populations studied. For 21 populations located at the north of the climatic hinge flowering was occurring during the dry season. The analysis of herbarium collections revealed a significant shift in the timing of flowering with latitude for E. suaveolens, and with the timing of the dry season for M. excelsa (and to a lesser extent L. alata), with the coexistence of two flowering peaks near the equator where the distribution of monthly rainfall is bimodal. For the other species, none of latitude, longitude or timing of the dry season had an effect on the timing of flowering. Our study highlights the need to identify the drivers of the flowering phenology of economically important African tree species.

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