Identification of sorting motifs of AtβFruct4 for trafficking from the ER to the vacuole through the Golgi and PVC

Although much is known about the molecular mechanisms involved in transporting soluble proteins to the central vacuole, the mechanisms governing the trafficking of membrane proteins remain largely unknown. In this study, we investigated the mechanism involved in targeting the membrane protein, AtβFructosidase 4 (AtβFruct4), to the central vacuole in protoplasts. AtβFruct4 as a green fluorescent protein (GFP) fusion protein was transported as a membrane protein during transit from the endoplasmic reticulum (ER) through the Golgi apparatus and the prevacuolar compartment (PVC). The N-terminal cytosolic domain of AtβFruct4 was sufficient for transport from the ER to the central vacuole and contained sequence motifs required for trafficking. The sequence motifs, LL and PI, were found to be critical for ER exit, while the EEE and LCPYTRL sequence motifs played roles in trafficking primarily from the trans Golgi network (TGN) to the PVC and from the PVC to the central vacuole, respectively. In addition, actin filaments and AtRabF2a, a Rab GTPase, played critical roles in vacuolar trafficking at the TGN and PVC, respectively. On the basis of these results, we propose that the vacuolar trafficking of AtβFruct4 depends on multiple sequence motifs located at the N-terminal cytoplasmic domain that function as exit and/or sorting signals in different stages during the trafficking process.     

Spatial, Temporal, and Economic Constraints to the Commercial Extraction of a Non–timber Forest Product: Copaíba (Copaifera spp.) Oleoresin in Amazonian Reserves

Spatial, Temporal, and Economic Constraints to the Commercial Extraction of a Non?CTimber Forest Product: Copaíba (Copaifera spp.) Oleoresin in Amazonian Reserves. The increasing prevalence of government?C and NGO?Csponsored programs to encourage commercial non?Ctimber forest product (NTFP) extractivism in the humid tropics has highlighted the need for ecological and socioeconomic appraisal of the viability of extractive industries. We adopted a novel integrative approach to examine NTFP resource potential and produced credible landscape?Cscale estimates of the projected value of an economically important Amazonian NTFP, the medicinal oleoresin of Copaifera trees, within two large contiguous extractive reserves in Brazilian Amazonia. We integrated results derived from previous spatial ecology and harvesting studies with socioeconomic and market data, and mapped the distribution of communities within the reserves. We created anisotropic accessibility models that determined the spatial and temporal access to Copaifera trees in permanently unflooded (terra firme) and seasonally flooded (várzea) forests. Just 64.9?% of the total reserve area was accessible, emphasizing the distinction between the actual resource stock and that which is available to extractors. The density of productive tree species was higher in the várzea forests, but per?Ctree productivity was greater in the terra firme forests, resulting in similar estimates of oleoresin yield per unit area (64?C67?ml?ha^?C1) in both forest types. A greater area of the várzea forests was accessible within shorter travel times of ??250 minutes; longer travel times allowed access to increasingly greater volumes of oleoresin from the terra firme forests. The estimated total volume of oleoresin accessible within the two reserves was 38,635 liters for an initial harvest, with projected offtake for a subsequent harvest falling to 8,274 liters. A household that extracted just 2 liters of oleoresin per month could generate 5?% of its mean income; market data suggested that certification could increase the value of the resource fivefold. Our approach is valuable in that it incorporates a range of methodologies and quantitatively accounts for the numerous constraints to the commercial viability of NTFP extraction.     

Farming in a rural settlement in central Italy: cultural and environmental implications of crop production through the transition from Lombard to Frankish influence (8th–11th centuries a.d.)

Plant macrofossil (carpological) and morphometric analyses were carried out on plant remains from the medieval castle of Miranduolo, Siena, a rural settlement in central Italy with a long sequence of occupation between the 8th and the 11th centuries a.d. The presence of Triticum aestivum/durum and Vicia faba var. minor from the first phase of the Lombard farming village suggests continuity with the agricultural tradition of the preceding Roman world, and the use of good cultivation techniques that allowed quality yields to be obtained from rather poor soils. At the same time, the significant presence of the primitive cereal T. monococcum, compared with the archaeobotanical literature of north-central Italy, allows to us consider it as a “cultural” element of Lombard farming. In the next cultural phases, with the Carolingian manor and then with the feudal castle, the stable presence of T. aestivum/durum and the reduction of T. monococcum in favour of more productive cereals such as Secale cereale and Hordeum vulgare indicate a further improvement in productivity. This is also confirmed by the appearance of fruits and nuts such as Castanea sativa, Vitis vinifera and Prunus persica. The increase in caryopsis sizes of T. monococcum and T. aestivum/durum in the transition from the village to the manorial phase is a consequence of the improvements in farming. The decrease in caryopsis size of T. monococcum from the manor phase to that of the castle testifies the decreasing importance of this cereal. The good date resolution of this research allows us to detect the crops, the storage and the processing practices, as well as the changing role of crop plants in the rural economy. This highlights the geographical, historical-cultural and political factors of the medieval transition from the Lombard to the Carolingian and then to the feudal period in central Italy.     

Phyto- and Zooplankton of Open Overgrown Shallows of the Rybinsk Reservoir Adjacent to a Mixed Grey Heron–Great Egret (<Emphasis Type="Italic">Ardea cinerea</Emphasis> L. and <Emphasis Type="Italic">A. alba</Emphasis> L.) Colony at a High Water Level

Phyto- and zooplankton communities developing in the open overgrown shallows of the Rybinsk Reservoir under the influence of a bird colony are shown to lose specific traits of quantitative characteristics and structure fluctuation in response to the elevated water level in contrast to previous findings. Possible reasons, such as the decomposition of sunken coastal vegetation playing the main role, accompanied by the development of semiaquatic macrophytes and trophic relations between algae and invertebrates, are discussed. It is found that increased atmospheric precipitation leads to an increased abundance of Copepoda in the zooplankton. Presumably, this effect correlates with more rapid and intensive inflow of avian vitality products rich in nitrogen into the water, resulting in a change in the stoichiometric ratio of nitrogen and phosphorus in zooplankton food objects to values favorable for copepods.