A long range restriction map of the distal human X chromosome short arm around the steroid sulfatase locus.

The distal short arm of the human X chromosome is of interest because it contains genes which escape X chromosome inactivation and because it is subject to frequent deletions in human patients. The steroid sulfatase gene has been particularly well studied as an example of a gene which escapes X inactivation and which is included in a number of these deletion events. For these reasons a physical map of the region around the STS gene would be of interest. We have constructed a rare cutting enzyme map of this area and have determined the position of several nearby markers with respect to STS. We have also oriented the 5' and 3' ends of the STS gene on this map and have determined the centromeric and telomeric portions of the region. Finally, we have shown that this map can be used to locate deletion breakpoints in STS deficient patients.     

Autoregulated changes in stability of polyribosome-bound beta-tubulin mRNAs are specified by the first 13 translated nucleotides.

The expression of tubulin polypeptides in animal cells is controlled by an autoregulatory mechanism whereby increases in the tubulin subunit concentration result in rapid and specific degradation of tubulin mRNAs. We have now determined that the sequences that are necessary and sufficient to specify mouse beta-tubulin mRNAs as substrates for this autoregulated instability reside within the first 13 translated nucleotides (which encode the first four beta-tubulin amino acids Met-Arg-Glu-Ile). This domain has been functionally conserved throughout evolution, inasmuch as sequences isolated from the analogous region of human, chicken, and yeast beta-tubulin mRNAs also confer autoregulation. Further, for an RNA to be a substrate for regulation, not only must it carry the 13-nucleotide coding sequence, but it must also be ribosome bound and its translation must proceed 3' to codon 41.     

Body weight deficit in the absence of reduction in cerebrum weight and nucleic acid content in progeny of swine restricted in protein intake during pregnancy

Fifty-six castrated male progeny of crossbred (Chester White x Landrace x Large White x Yorkshire) dams fed an adequate diet (control, C), a control diet fed at one-third of C (restricted, R), or diets severely deficient in protein (PF) or restricted in nonprotein calories (RCal) were killed at age 25 weeks. Dams were fed their respective diets in the following regimens: C, 1.8 kg (6000 kcal daily) throughout pregnancy; R, 0.6 kg of C diet daily for 70 days, then 1.8 kg of C daily to parturition at about 114 days; PF, 1.8 kg of a "protein-free" diet (less than 0.2% protein) throughout pregnancy; RCal, 0.6 kg daily (2000 kcal) of a diet containing three times the concentration of protein, minerals, and vitamins provided by the C diet for 70 days, then 1.8 kg of C daily to parturition. All dams were fed an adequate diet ad libitum through a 28-day lactation. Castrated male progeny were assigned to one of two replicates based on birth date and fed a corn-soybean meal diet ad libitum from weaning to age 25 weeks, supplemented from age 10 to 12 weeks with 0, 110, or 220 mg/kg of thyroprotein (iodinated casein). Cerebrum weight was unaffected by maternal diet, despite a significant (P less than 0.001) reduction in body weight of progeny of PF dams compared with other groups, resulting in a higher relative cerebrum weight in progeny of PF dams than in progeny of C, R, and RCal dams. Absolute and relative weights of RNA, DNA, and total protein in cerebrum were unaffected by maternal diet. Thyroprotein supplementation to the diet of the progeny had no effect on cerebrum weight or its protein or nucleic acid content. It is concluded that maternal protein deprivation but not restriction of feed or nonprotein calorie intake to one-third of recommended allowance during gestation results in stunting of body weight in young adult progeny but does not affect cerebrum weight, cerebrum cell number (DNA), or protein synthetic activity (RNA), or RNA-to-protein ratio.     

Metastasis-associated alterations in phospholipids and fatty acids of human prostatic adenocarcinoma cell lines.

Metastatic variants of human prostatic adenocarcinoma cell lines (DU-145, LNCaP, and ND-1) were studied by using soft agar colony forming efficiency, nude mice tumorigenicity, in vitro invasion assay, and type IV collagenase assay. The DU-145 and ND-1 cell line showed higher metastatic potential than LNCaP. Lipids from DU-145, ND-1, and LNCaP cells were extracted and analyzed by thin-layer chromatography and gas-liquid chromatography. The major lipids were phosphatidylcholine, phosphatidylethanolamine, sphingomyelin, fatty acids, and cholesterol. The sphingomyelin level was significantly higher in highly metastatic cells (DU-145 and ND-1) compared with the lower metastatic variant (LNCaP). The increase in the synthetic pathway and decrease in degradation pathway of sphingomyelin in microsomal fractions was sufficient to account for the measured increase in sphingomyelin in DU-145 cells compared with LNCaP cells. The major fatty acids of these lipids were palmitic (16:0), stearic (18:0), oelic (18:1), and arachidonic acid (20:4). The arachidonic acid level was significantly decreased in DU-145 and ND-1 compared with LNCaP cells. Electron microscopic studies showed no significant changes in the morphology of DU-145, ND-1, and LNCaP cells. The results of these investigations demonstrate for the first time that sphingomyelin and arachidonic acid contents are different in high and low metastatic variants of human prostatic adenocarcinoma cell lines.     

Impacts of section 404 permits requiring compensatory mitigation on wetlands in California (USA)

We analyzed data from Section 404 permits issued in California from January 1971 through November 1987 that involved impacts to wetlands and required compensatory mitigation (wetland creation, restoration, or preservation). The purpose of this study was to determine patterns and trends in permitting activity and to document cumulative effects of associated management decisions on the California wetland resource. The 324 permits examined documented that 387 compensatory wetlands (1255.9 ha) were required as mitigation for impacts to 368 wetlands (1176.3 ha). The utility of the data on wetland area was limited, however, since 38.0% of the impacted wetlands and 41.6% of the compensatory wetlands lacked acreage data. The wetland type most frequently impacted (37.8% of impacted wetlands) and used in compensation (38.2% of compensatory wetlands) was palustrine forested wetlands. Estuarine intertidal emergent wetlands had the most area impacted (52.3%) and compensated (62.5%). The majority of the wetlands were small (less than or equal to 4.0 ha in size). Wildlife habitat was the most frequently listed function of impacted wetlands (90.7% of the permits) and objective of compensatory wetlands (83.3%). Endangered species were listed as affected in 20.4% of impacted and 21.0% of compensatory projects. The number of permits requiring compensatory mitigation and the number of impacted and compensatory wetlands increased from 1971 to 1986.Documentation of the details of Section 404 permit decisions was inadequate for the permits we examined. Area information and specific locations of impacted and compensatory wetlands were lacking or of poor quality. Follow-up information was also inadequate. For example, project completion dates were specified in the permit for only 2.2% of compensatory wetlands. Furthermore, less than one-third (31.5%) of the permits required the compensatory wetland to be monitored by at least one site visit. We recommend improved documentation, regular reporting, and increased monitoring for better evaluation of the Section 404 permitting system.     

Identification and characterization of an {alpha}-mannosidase from Trypanosoma cruzi

In this report we describe the first purification and characterizationof the acid -mannosidase from the human parasite Trypanosomacruzi. The purified enzyme exhibited a native mol. wt of 240000 Da and is apparently composed of four identical subunitsof mol. wt 58 000 Da. Each of the four subunits contains oneN-linked high-mannose-type oligosaccharide. The -mannosidaseexhibited a pH optimum of 3.5 and a pI of 5.9. This low pH optimumand the ability of swainsonine to inhibit its activity suggestthat the -mannosidase is a lysosomal enzyme. Antibodies againstthe T.cruzi enzyme did not react with mammalian lysosomal -mannosidaseand, conversely, antibody against a rat lysosomal -mannosidasedid not react with the T.cruzi enzyme. Thus, the T.cruzi enzymeappears to be distinct from its mammalian counterpart. -mannosidase lysosomal enzyme Trypanosoma cruzi