Anhidrotic ectodermal dysplasia as autosomal recessive trait in an inbred kindred

Anhidrotic ectodermal dysplasia in an inbred kindred was observed in three sisters and three first cousins. This was interpreted as presumptive evidence for autosomal recessive inheritance and it is suggested that in addition to its known genes, anhidrotic ectodermal dysplasia occasionally may be caused by an autosomal recessive gene.This investigation was supported by Public Health Service Research Grant No. FR 00123, from GCRC-DRFR and by a Fellowship in Pediatric Teratology of the Children's Hospital Research Foundation, Cincinnati.     

A novel approach to the analysis of the initiation of embryo development in gramineae

An in vivo model system to study the initiation of embryo development is presented. From the so-called Salmon system of wheat (alloplasmic lines with a 1BL-1RS chromosome translocation), three completely isogenic and homozygous lines were produced by selection for uniformity in about 20 selfing/backcross generations as well as between sublines of doubled haploids. The line (aestivum)-Salmon is male fertile and sexual. The lines (caudata)-Salmon and (kotschyi)-Salmon are male sterile and have a parthenogenetic capacity of about 90%. The expression of nuclear-cytoplasmic male sterility is different for the two parthenogenetic lines. The initiation of autonomous embryo development at defined developmental stages of the ovaries and the maximum degree of parthenogenesis are identical in both parthenogenetic lines as proved by the auxin test and progeny analyses. The protein patterns from ovary extracts of the three isogenic lines were identical for more than 200 spots of 2-D polyacrylamide gels, confirming their homogeneity. However, one protein (P 115.1) was found 3 days before and during anthesis only in ovaries of the parthenogenetic lines. It seems to be involved in the initiation of parthenogenesis.     

Fluorescent labelling of sequencing primers for automated oligonucleotide synthesis.

A fluorescein derivative is described which can be used as a normal phosphoramidite in oligonucleotide synthesis, giving high yields of fluorescein labelled sequencing primers. The labelled primers were used in automated DNA-sequence analysis without modification of existing protocols, the computer-processed sequences being reproducibly readable up to 400 bases. The procedure described makes the fluorescent labelling of oligonucleotides much easier, and the time of labelling can be significantly reduced. It speeds up the "primer walking" approach of automated DNA sequencing.     

Uncoupling activity and physicochemical properties of derivatives of fluazinam.

The physico-chemical properties and uncoupling activity of eight derivatives of N-phenyl-2-pyridinamines related to the fungicide fluazinam were analyzed using rat liver mitochondria. The uncoupling activity of these compounds relies on the deprotonable secondary amino group. One of the derivatives tested (B-3) was slightly more efficient than fluazinam. By phase-distribution analysis we could show that the N-phenyl-2-pyridinamines are chemicals with moderate hydrophobicity. Deprotonation of the compound reduces the water/octanol partition coefficient by about one order of magnitude. The pKA value of the deprotonable group is affected equally by electron withdrawing substituents of the phenyl- and the pyridinyl-ring, and could be predicted simply from the sum of the Hammett coefficients. The uncoupling efficiency was not dependent on the hydrophobicity of the compound, but appeared to be governed by the pKA of the deprotonable group. This structure/uncoupling characteristic is different from that of the generally more hydrophobic uncouplers of the salicylanilide-type. The pKA resulting in the most efficient uncoupling was found to lie in the range of the pH of the reaction medium. A model based on a solution complexation mechanism, which describes this behaviour, is presented. We conclude that the N-phenyl-2-pyridinamines uncoupled the mitochondria by a simple protonophoric cycle involving protonation/deprotonation in the bulk phase, and that the kinetics of uncoupling were primarily governed by the total concentration of the limiting uncoupler species.     

Alteration by centric fission of the diploid chromosome number in Vicia faba L.

An individual with a diploid chromosome complement of 2n=14 instead of 2n=12 is deseribed for the broad bean Vicia faba L. This karyotypic deviation resulted from centromere splitting of the wildtype metacentric satellite chromosome pair as demonstrated by Giemsa banding pattern. It is the first case of centric fission observed in this species. Our data support the hypothetic mechanism of Robertsonian rearrangements suggested by Holmquist and Dancis (Genetica 52–53: 151–163, 1980).     

Enzymes of amide and ureide biogenesis in developing soybean nodules

Amide and ureide biogenic enzymes were measured in the plant fraction of soybean (Glycine max) nodules during the period 11 to 23 days after inoculation with Rhizobium japonicum (USDA 3I1b142). Enzymes involved in the initial assimilation of ammonia, i.e. glutamine synthetase, glutamate synthase, and aspartate aminotransferase, showed substantial increases in their specific activities over the time course. These increases paralleled the induction of nitrogenase activity in the bacteroid and leghemoglobin synthesis in the plant fraction. The specific activity of asparagine synthetase, however, showed a rapid decline after an initial increase in specific activity. Following the initial increases in the ammonia assimilatory enzymes, there was an increase in the activity of 5-phosphoribosylpyrophosphate amidotransferase, the enzyme which catalyzes the first committed step of de novo purine biosynthesis. This was followed by a dramatic increase in the purine oxidative enzymes, xanthine dehydrogenase and uricase. Smaller increases were observed in the activities of enzymes associated with the supply of metabolites to the purine biosynthetic pathway: phosphoglycerate dehydrogenase, serine hydroxymethylase, and methylene tetrahydrofolate dehydrogenase.     

Structure and origin of a snapback defective interfering particle RNA of vesicular stomatitis virus

The nucleotide sequence of the region which covalently links the complementary strands of the "snapback" RNA of vesicular stomatitis virus, DI011, is (Formula: see text). Both strands of the defective interfering (DI) particle RNA were complementary for their full length and were covalently linked by a single phosphate group. Because the strands were exactly the same length and complementary, template strand and daughter strand nucleocapsids generated during replication of DI 011 were undistinguishable on the basis of sequence, a property not shared by other types of DI particle RNAs. Treatment of the RNA with RNase T1 in high-ionic-strength solutions cleaved the RNA only between positions 1 and 1'. These results and the availability of the guanosine residue in position 1' to kethoxal, a reagent that specifically derivatizes guanosines of single-stranded RNA, suggest that steric constraints keep a small portion of the "turnaround" region in an open configuration. The sequence of the turnaround region was not related in any obvious way to the sequences at the 3' and 5' termini and limited the number of possible models for the origin of this type of DI particle RNA. Two models for the genesis of DI 011 RNA are discussed. We favor one in which the progenitor DI 011 RNA was generated by replication across a nascent replication fork.     

Effects of lanthanum on calcium-dependent phenomena in human red cells.

Lanthanum (0.25 mM) does not penetrate into fresh or Mg2+-depleted cells, whereas it does into ATP-depleted or ATP + 2,3-diphosphoglycerate-depleted cells, into cells containing more than 3 mM calcium, or cells stored for more than 4 weeks in acid/citrate/dextrose solution. In fresh cells loaded with calcium, extracellular lanthanum blocks the active Ca2+-efflux completely and inhibits (Ca2+ + Mg2+)-ATPase (ATP phosphohydrolase, EC 3.6.1.3) activity to about 50%. In Mg2+-depleted cells Ca2+-Ca2+ exchange is inhibited by lanthanum. Ca2+-leak is unaffected by lanthanum up to 0.25 mM concentration; higher lanthanum concentrations reduce leak rate. In NaCl medium Ca2+-leak +/ S.D. amounts to 0.28 +/ 0.08 mumol/1 of cells per min, whereas in KC1 medium to 0.15 +/ 0.04 mumol/1 of cells per min at 2.5 mM [Ca2+]e and 0.25 mM [La3+]e pH 7.1. Lanthanum inhibits Ca2+-dependent rapid K+ transport in ATP-depleted and propranolol-treated red cells, i.e. whenever intracellular calcium is below a critical level. The inhibition of the rapid K+ transport can be attributed to protein-lanthanum interactions on the cell surface, since lanthanum is effectively detached from the membrane lipids by propranolol. Lanthanum at 0.2--0.25 mM concentration has no direct effect on the morphology of red cells. The shape regeneration of Ca2+-loaded cells, however, is blocked by lanthanum owing to Ca2+-pump inhibition. Using lanthanum the transition in cell shape can be quantitatively correlated to intracellular Ca2+ concentrations.     

Influence of the hormone analogue 13-NLE-molitin and of 1-methyl-3-isobutylxanthine on tone and cyclic 3',5'-AMP content of antral and duodenal muscles in the rabbit.

1. By the action of 1-methyl-3-isobutylxanthine (isobutyltheophylline, 2 - 3 × 10⁻⁴ M), the content of cyclic 3', 5'-AMP in the antral and duodenal muscles of the rabbit is increased by 72 % and 126 %, respectively; by 1.8 × 10⁻⁷ M 13-norleucine-motilin and 1.8 × 10⁻⁶ M acetylcholine it is not changed. 13-norleucine-motilin is an analogue of the recently discovered duodenal tissue hormone motilin and has identical effects. 1-methyl-3-isobutylxanthine has a more powerful inhibiting effect on phosphodiesterase than has theophylline.2. 3 × 10⁻⁴ M isobutyltheophylline reduces the tone of the duodenal muscle while simultaneously increasing the content of cyclic AMP and negates the tone-enhancing effect of nle-motilin on the duodenal muscle, while nle-motilin increases the muscle tone lowered by isobutyltheophylline.3. The basic tone of the antral muscle is not reduced by isobutyltheophylline. However, the contraction-promoting effect of nle-motilin after an increase in cyclic AMP due to isobutyltheophylline is significantly lower.4. It is assumed that the changes in the tone or in the response of the antral and duodenal muscles to nle-motilin observed after the administration of isobutyltheophylline, are due to the increase of cyclic AMP in the tissue.5. The antagonistic effects of cyclic AMP and motilin on the gastro-intestinal muscles might be of physiological importance for the regulation of the gastro-intestinal motor activity.