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Allegheny Vine Adlumia fungosa (Fumariaceae) is reported new to Louisiana, U.S.A.

Isoprenylated proteins have important functions in cell growth and differentiation of eukaryotic cells. Inhibitors of protein prenylation in malaria have recently shown strong promise as effective antimalarials. In studying protein prenylation in the malaria protozoan parasite Plasmodium falciparum , we have shown earlier that the incubation of P. falciparum cells with 3 H-prenol precursors resulted in various size classes of labeled proteins. To understand the physiological function of prenylated proteins of malaria parasites, that are targets of prenyltransferase inhibitors, we searched the PlasmoDB database for proteins containing the C-terminus prenylation motif. We have identified, among other potentially prenylated proteins, an orthologue of a PRL (protein of regenerating liver) subgroup protein tyrosine phosphatases, termed PfPRL. Here, we show that PfPRL is expressed in the parasite's intraerythrocytic stages, where it partially associates with endoplasmic reticulum and within a subcompartment of the food vacuole. Additionally, PfPRL targeting parallels that of apical membrane antigen-1 in developing merozoites. Recombinant PfPRL shows phosphatase activity that is preferentially inhibited by a tyrosine phosphatase inhibitor suggesting that PfPRL functions as a tyrosine phosphatase. Recombinant PfPRL can also be farnesylated in vitro . Inhibition of malarial farnesyltransferase activity can be achieved with the heptapetide RKCHFM, which corresponds to the C-terminus of PfPRL. This study provides the first evidence for expression of enzymatically active PRL-related protein tyrosine phosphatases in malarial parasites, and demonstrates the potential of peptides derived from Plasmodium prenylated proteins as malarial farnesyltransferase inhibitors.

Middle Archaic earthen mound complexes in the lower Mississippi valley are remote antecedents of the famous but much younger Poverty Point earthworks. Watson Brake is the largest and most complex of these early mound sites. Very extensive coring and stratigraphic studies, aided by 25 radiocarbon dates and six luminescence dates, show that minor earthworks were begun here at ca. 3500 B.C. in association with an oval arrangement of burned rock middens at the edge of a stream terrace. The full extent of the first earthworks is not yet known. Substantial moundraising began ca. 3350 B.C. and continued in stages until some time after 3000 B.C. when the site was abandoned. All 11 mounds and their connecting ridges were occupied between building bursts. Soils formed on some of these temporary surfaces, while lithics, fire-cracked rock, and fired clay/loam objects became scattered throughout the mound fills. Faunal and floral remains from a basal midden indicate all-season occupation, supported by broad-spectrum foraging centered on nuts, fish, and deer. All the overlying fills are so acidic that organics have not survived. The area enclosed by the mounds was kept clean of debris, suggesting its use as ritual space. The reasons why such elaborate activities first occurred here remain elusive. However, some building bursts covary with very well-documented increases in El Niño/Southern Oscillation events. During such rapid increases in ENSO frequencies, rainfall becomes extremely erratic and unpredictable. It may be that early moundraising was a communal response to new stresses of droughts and flooding that created a suddenly more unpredictable food base.

An 11-mound site in Louisiana predates other known mound complexes with earthen enclosures in North America by 1900 years. Radiometric, luminescence, artifactual, geomorphic, and pedogenic data date the site to over 5000 calendar years before present. Evidence suggests that the site was occupied by hunter-gatherers who seasonally exploited aquatic resources and collected plant species that later became the first domesticates in eastern North America.

We conducted a telemetry study of subadult alligator snapping turtles (Macroclemys temminckiz) to investigate movement and habitat use. Available habitat consisted of baldcypress forest (Taxodium distichum) (69.1%) and open channel (30.9%). Twelve (three male, nine female) turtles from Bayou Desiard in northeast Louisiana were each equipped with an ATS external radio transmitter and returned to the capture location within 2 h. A total of 1327 location fixes were recorded from March 1992 toJune 1993. At each fix location the date, time, water temperature and depth, direction from last fix and capture site, and nearest shoreline, and habitat were recorded. Significant differences were noted between male and female mean fix distance (males = 352.2 m, females = 160.3 m), mean percentage of movement fixes (males = 62.7%, females = 42.7%) and mean home range length (males = 3495.1 m, females = 1423.2 m). The percentage of movement fixes and fix distance was highly correlated with water temperature but not with the size of the turtle. Turtles preferred the baldcypress forest to open channel. Males and females had significant differences in microhabitat use; 56.1% of male fixes were associated with structures (e.g., logs) compared to 79.7% for females. Turtles returned to specific microsites and there were no overland movements. Subadult and adult alligator snapping turtles in Bayou Desiard have similar movement patterns and habitat use.