ERRATA

p. 210. alternatus ... This entry is out of alphabetical orderand should follow after alsiosus. p. 225. caracteristicus. For x read xi. p. 236. cutis-auguina. Read cutis-anguina. p. 247. fabula. After Chem. add ) p. 271. maculosus Sow. Delete 3*. p. 279. muriculatus Sow. Delete 1. p. 302. reissi. For Sauto read Santo. p. 311. stercutius. Delete full stop after as.     

ERRATA

p. 1284. Fig. 1, values on the ordinate (Leaf extension rate,mm h^–1): scale should be moved down so that zero lieson the x-axis ... LER = 3.2 {1 – exp [–4 (S – 0.41)]}...     

ERRATA

Effects of coupled solute and water flow in plant roots withspecial reference to Brouwer's experiment. Edwin L. Fiscus. p. 71 Abstract: Line 3 delete ‘interval’ insert‘internal’. p. 73 Materials and Methods: line 6: delete ‘diversion’ insert ‘division’ line 9 equation should read J_v=L_p P–RT(C⁰–C¹). 74 Last line of figure legend: 10^–1 should read 10^–11. 75 Line 11: delete ‘seems’ insert ‘seem’. le 1 column heading—10⁶ should read 10¹¹. 77 delete ‘...membrane in series of...’ insert ‘membranein series or...’ Delete final paragraph.     

ERRATA

p. 136, 1. 25, for bombayana (Melvill) read bombayana (Sowerby). p. 138, 1. 24, for Trophora read Triphora. p. 255, 1. 6, for 1853 read 1856.      

ERRATA

p. 5, l. 22 for Dr. Frank read Dean p. 48, footnote 10 for Oxyxypræa read Oxyeypræa p. 51, footnote 18 for Dantzenberg read Dautzenberg p. 77, l. 29 for toxodont read taxodont p. 194, l. 10 for Rhytidia read Rhytida p. 227, l. 24 for chronological read conchological      

ERRATA

p. 1, 1. 23, for Specimens read Specimens. p. 58, last line, for 15th March, read 13th March. p. 60, 1. 2, for Toredo read Teredo. p. 141, 1. 35, for Plates I and II read Plates 13 and 14. p. 142, 1. 3, for Plate 4 read Plato 16. p. 142, 1. 4, for Plate 4, 5, read Plate 16, 5.      

Protein-O-glycosylation in yeast: protein-specific mannosyltransferases

S.cerevisiae contains at least six genes (PMT1–6) fordolicholphosphate-D-mannose: protein-O-D-mannosyltransferases.The in vivo mannosylation of seven O-mannosylated yeast proteinshas been analyzed in a number of pmt mutants. The results clearlyindicate that the various protein O-mannosyltransferases havedifferent specificities for protein substrates. Five of theproteins tested (chitinase, a-agglutinin, Kre9p, Bar1p, Pir2p/hsp150)are mainly underglycosylated in pmt1 and pmt2 mutants, wherebyqualitative differences exist among the various proteins. Twoof the O-mannosylated proteins (Ggp1p and Kex2p) are not atall affected in pmt1 and pmt2 mutants but are clearly underglycosylatedwhen PMT4 is mutated. Although the PMT4 gene product is shownto be responsible for O-mannosylating a Ser-rich region of Ggp1pin vivo, a penta-seryl-peptide is not an in vitro substratefor this transferase. A PMT3 mutation does affect O-manno-sylationof chitinase only in the genetic background of a pmt1pmt2 doublemutation, indicating that PMT1 and PMT2 can compensate for adeleted PMT3 gene. dolichol-phosphate PMT gene family protein glycosylation S. cerevisiae     

锡林郭勒草原布氏田鼠体蚤和巢蚤数量动态及蚤类群落演替

1989～1998年对内蒙古阿巴嘎旗那仁宝力格苏木布氏田鼠Microtus brandti体蚤和巢蚤的数量进行了调查和分析,所得体蚤包括3科7属9种, 其中优势种有: 原双蚤田野亚种Amphipsylla primaris mitis占41.84%, 近代新蚤东方亚种Neopsylla pleskei orientalis占41.18%, 光亮额蚤Frontopsylla luculenta占13.18%。所得巢蚤包括2科6属9种, 其中优势种近代新蚤占74.94%; 光亮额蚤占10.04%, 原双蚤占8.20%, 宽圆纤蚤Rhadinopsylla rothschildi占6.44%, 是常见种。田鼠体的原双蚤、近代新蚤、光亮额蚤和体蚤指数间呈正相关(P<0.05)。田鼠巢的近代新蚤、光亮额蚤、宽圆纤蚤和巢蚤指数间正相关显著(P<0.01)。春季巢蚤指数∶春季体蚤指数≈5∶1, 秋季巢蚤指数∶秋季体蚤指数≈75∶1。近代新蚤既是体型蚤又是巢型蚤, 为田鼠的优势蚤种; 原双蚤数量占体蚤的 41.84%, 是体型蚤; 光亮额蚤为体蚤和巢蚤中的常见种。     

ERRATA

June Number: p. 276, last line, for 9–16 read 9–12. p. 279, l. 16, for Pterocera amantia read Pterocera aurantia.      

Scanning electron microscopy of Heterocapsa pygmaea sp. nov., and evidence for polyploidy as a speciation mechanism in dinoflagellates

The thecal morphology of three isolates of the marine dinoflagellateHeterocapsa pygmaea sp. nov. are here examined by manning electronand light microscopy. The thecal tabulation of these isolatesis p.p., c.p., 5', 3a, 7', 6c, a.s., r.s., l.a.s., l.p.s.,[?a.a.s. and p.a.s.], 5' ' and 2' ' and is identical to thatof H. niei and H. illdefina. The assignment of thecal platesto various series is based on interpretation of plate homologiesamong peridinioid genera. The above formula represents the basicpattern for Heterocapsa. The cell dimensions of four Heterocapsaspecies are determined; Heterocapsa pygmaea is the smallestspecies. Heterocapsa pygmaea differs from the next largest species,H. niei, in having approximately half the number of chromosomesand as such can be interpreted as a case of polyploidy. If so,this is the first evidence of polyploidy as a speciation mechanismin the Pyrrhophyta. ¹Present address: Department of Botany, Duke University, DurhamNorth Carolina 27706 ²Present address: The Biological Laboratories, Harvard University,Cambridge, Massachusetts 02138     

Zinc status affects p53, gadd45, and c-fos expression and caspase-3 activity in human bronchial epithelial cells

This study was designed to examine theinfluence of zinc depletion and supplementation on the expression ofp53 gene, target genes of p53, andcaspase-3 activity in normal human bronchial epithelial (NHBE) cells. Aserum-free, low-zinc medium containing 0.4 µmol/l of zinc [zincdeficient (ZD)] was used to deplete cellular zinc over one passage. Inaddition, cells were cultured for one passage in media containing 4.0 µmol/l of zinc [zinc normal (ZN)], which represents normal cultureconcentrations (Clonetics); 16 µmol/l of zinc [zinc adequate (ZA)],which represents normal human plasma zinc levels; or 32 µmol/l ofzinc [zinc supplemented (ZS)], which represents the high end ofplasma zinc levels attainable by oral supplementation in humans.Compared with ZN cells, cellular zinc levels were 76% lower in ZDcells but 3.5-fold and 6-fold higher in ZA and ZS cells, respectively.Abundances of p53 mRNA and nuclear p53 protein were elevatedin treatment groups compared with controls (ZN). For p53mRNA abundance, the highest increase (3-fold) was observed in ZD cells.In contrast, the highest increase (17-fold) in p53 nuclearprotein levels was detected in ZS cells. Moreover, gadd45mRNA abundance was moderately elevated in ZD and ZA cells and was notaltered in ZS cells compared with ZN cells. Furthermore, the onlyalteration in c-fos mRNA and caspase-3 activity was thetwofold increase and the 25% reduction, respectively, detected in ZScompared with ZN cells. Thus p53, gadd45, andc-fos and caspase-3 activity appeared to be modulated bycellular zinc status in NHBE cells.

     

A Novel Gene, ITM, Located between p57KIP2 and IPL, Is Imprinted in Mice

We searched for new imprinted genes using a positional cloningmethod in a region of human chromosome 11p15.5, which containsseveral imprinted genes including p57^KIP2 and IPL, and founda novel ITM gene located between p57^KIP2 and IPL. We also obtainedthe mouse homologue Itm in itss yntenic region of mouse chromosome7. In humans, its location is 17 kb centromeric to p57^KIP2 and3 kb telomeric to IPL, and in mice, 15 kb and 2.5 kb, respectively.They are expressed in most tissue, but especially in the kidneyand liver, and moderately in the heart, lung and testis. Miceexhibit a functional imprinting resulting in higher expressionof maternal alleles in fetal, newborn and most adult tissues,but it is biallelically expressed in the adult kidney and liverwhere expression is the highest. In addition to the discrepancybetween the level of expression and the strength of the imprint,Itm has several unusual features for an imprinted gene, includinglarge introns, moderate GC content and the absence of directrepeats. Our results will be helpful in understanding the intricateregulatory mechanism of imprinted genes.     

Vegetable Plant Part Relationships. III. Modification of Carrot (Daucus carota L.) Root and Shoot Weights by Gibberellic Acid and Daminozide

Aqueous foliar sprays of N-dimethylaminosuccinamic acid (daminozide)at 2000 p.p.m. and gibberellic acid (GA) at 100 p.p.m. wereapplied 45, 59, 82 and 100 days after sowing to Chantenay carrotswith population densities of 244, 495 and 883 plants m^–2.The plants were harvested on ten approximately weekly occasions;fresh weights were determined and d. wt estimates were obtainedfor the separated shoots (s) and roots (r). Allometric linearregressions of the logarithm of s on that of r at each harvestseparately, clearly showed that GA always increased shoot: rootratio and reduced root yield (by approximately 35 per cent)but could sometimes also increase whole-plant weight. Daminozideincreased root yield (by approximately 7 per cent from 80 tonnesha^–1) and tended to have effects opposite to those ofGA. Daucus carota L., carrot, root weight, shoot weight, N-dimethylaminosuccinamic acid (daminozide), gibberellic acid     

Amino acids stimulate phosphorylation of p70S6k and organization of rat adipocytes into multicellular clusters

In previousstudies we have shown that rat adipocytes suspended in Matrigel andplaced in primary culture migrate through the gel to form multicellularclusters over a 5- to 6-day period. In the present study,phosphorylation of the insulin-regulated 70-kDa ribosomal protein S6kinase (p70^S6k) was observedwithin 30 min of establishment of adipocytes in primary culture. Twoinhibitors of the p70^S6ksignaling pathway, rapamycin and LY-294002, greatly reducedphosphorylation of p70^S6k andorganization of adipocytes into multicellular clusters. Of all thecomponents of the cell culture medium, amino acids, and in particular asubset of neutral amino acids, were found to promote bothphosphorylation of p70^S6k andcluster formation. Lowering the concentrations of amino acids in themedium to levels approximating those in plasma of fasted rats decreasedboth phosphorylation of p70^S6kand cluster formation. Furthermore, stimulation ofp70^S6k phosphorylation by aminoacids was prevented by either rapamycin or LY-294002. These findingsdemonstrate that amino acids stimulate thep70^S6k signaling pathway inadipocytes and imply a role for this pathway in multicellularclustering.

     

A new Dol-P-Man:protein O-D-mannosyltransferase activity from Saccharomyces cerevisiae

The deletion of the protein mannosyltransferase 1 gene (PMT1)of Saccharomyces cerevisiae results in viable cells. O-Mannosylationof proteins is reduced to about half of the value in comparisonto wild-type cells. In order to distinguish between the thePMT1 gene product (= Pmt1p) and residual transferase activity,an in vitro assay to measure Dol-P-Man:protein mannosyltransferaseactivity in cells deleted for PMT1 has been developed. The transferaseactivity of these cells exhibits a pH optimum of 6.5 as comparedto pH 7.5 for Pmt1p. The K_$$$ value of the residual enzyme activityfor the hexapeptide YNPTSV is 7 times higher than that of Pmt1pand shows a clear preference for the seryl/residue. Differencesin substrate affinities as well as in seryl/threonyl preferencebetween the two enzymes, however, depend on the specific sequenceof the peptides used in the enzyme assay. The new enzyme activityshows a significantly lower thermal stability as compared toPmt1p. glycoprotein O-glycosylation mannosyltranferase Saccharomyces cerevisiae