Field response of tomato (Lycopersicon esculentum Mill ‘Pusa Ruby’) to inoculation with a VA mycorrhizal fungusGlomus fasiculatum and withAzotobacter vinelandii

Summary The response of tomato (Lycopersicon esculentum Mill) to inoculation with the vasicular arbuscular mycorrhizal (VAM) fungusGlomus fasiculatum andAzotobacter vinelandii singly and in combination was tested in the field. It was found thatG. fasiculatum as well asA. vinelandii significantly increased leaf area, shoot dry weight, nitrogen content phosphorus content and yield in respect to uninoculated control. While, VAM fungal treatment alone could bring about substantial increase in growth, nitrogen content, phosphorus content and yield, its combination withA. vinelandii produced additional effects on leaf area, shoot dry weight, phosphorus content and yield. Contribution No. 304/83 of Indian Institute of Horticultural Research, Bangalore-89.     

Regional chromosomal assignment of human renin gene to 1q12----qter and use in linkage studies in Charcot-Marie-Tooth disease

The gene for renin, previously mapped to human chromosome 1, was further localized to 1q12----qter using human-mouse somatic cell hybrid DNAs. The renin DNA probe used (lambda HR5) could detect a HindIII restriction fragment length polymorphism. When used in studies of 12 informative families, no linkage could be found between the renin gene and Charcot-Marie-Tooth disease. Furthermore, an association of any renin allele with hypertension was not apparent.     

Assignment of the prealbumin (PALB) gene (familial amyloidotic polyneuropathy) to human chromosome region 18q11.2–q12.1

Summary The assignment of the human prealbumin (PALB) gene to chromosome region 18q11–q12.1 has been achieved using a human genomic probe in the study of human-mouse somatic cell hybrids and by in situ hybridization. Because familial amyloidotic polyneuropathy was reported previously to be due to a mutation in prealbumin, it can be inferred that the gene for this disorder also maps to 18q11.2–q12.1.     

Assignment of cathepsin E (CTSE) to human chromosome region 1q31 by in situ hybridization and analysis of somatic cell hybrids

A full length cathepsin E (CTSE) cDNA clone was used to assign the corresponding gene to human chromosome region 1q31 by in situ hybridization. Southern blot analysis of DNA from three independent human x rodent somatic cell hybrids containing X;1 translocations confirmed the assignment of the CTSE gene to the distal region of the long arm of chromosome 1.     

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.     

Chromosomal distribution of three members of the human natriuretic peptide receptor/guanylyl cyclase gene family

Chromosomal localization of the genes encoding three homologous human proteins, the ANPRA, ANPRB, and ANPRC cell surface receptors, was determined by polymerase chain reaction (PCR) analysis of genomic DNA from somatic cell hybrids. The ANPRA gene was assigned to 1q12----qter by intron-specific PCR. The ANPRB gene was assigned to 9p11----p22 using species-specific length variation in PCR fragments. The ANPRC gene was assigned to chromosome 5 using human-specific PCR primers identified by screening a human primer panel on parental DNA samples (shotgun primer screening). Chromosomal assignments based on PCR analysis were confirmed and the genes further sublocalized by in situ hybridization of cloned cDNA probes to human metaphase chromosomes. The ANPRA gene was sublocalized to 1q21----q22, the ANPRB gene to 9p12----p21, and the ANPRC gene to 5p13----p14.     

Cloning of cDNAs for human phosphoribosylpyrophosphate synthetases 1 and 2 and X chromosome localization of PRPS1 and PRPS2 genes

Cloned cDNAs representing the entire, homologous (80%) translated sequences of human phosphoribosylpyrophosphate synthetase (PRS) 1 and PRS 2 cDNAs were utilized as probes to localize the corresponding human PRPS1 and PRPS2 genes, previously reported to be X chromosome linked. PRPS1 and PRPS2 loci mapped to the intervals Xq22-q24 and Xp22.2-p22.3, respectively, using a combination of in situ chromosomal hybridization and human x rodent somatic cell panel genomic DNA hybridization analyses. A PRPS1-related gene or pseudogene (PRPS1L2) was also identified using in situ chromosomal hybridization at 9q33-q34. Human HPRT and PRPS1 loci are not closely linked. Despite marked cDNA and deduced amino acid sequence homology, human PRS 1 and PRS 2 isoforms are encoded by genes widely separated on the X chromosome.     

Effect of presowing seed treatment with molybdenum and cobalt on growth,nitrogen and yield in bean (Phaseolus vulgaris L.)

Summary Bean (Phaseolus vulgaris L. Cv. Burpees Stringless) seeds were subjected to two cycles of presowing soaking and drying treatments with sodium molybdate and cobalt nitrite at 1 and 5 ppm concentrations used separately and also in combination. Sodium molybdate 2 ppm and cobalt nitrite 1 ppm used singly proved better than the remaining treatments with respect to nodulation, dry matter, nitrogen and yield. Combined treatment with sodium molybdate and cobalt nitrite did not produce additive effect on any parameter studied compared to their usage alone.     

Regional localisations and linkage relationships of seven RFLPs and myotonic dystrophy on chromosome 19

Summary We have studied the genetic linkage relationships of seven DNA polymorphisms on chromosome 19, with each other and with the myotonic dystrophy locus. The DNA sequences were localised to various regions of the chromosome using translocations in somatic cell hybrids. These results provide the basis for a linkage map of most of chromosome 19, and suggest that the myotonic dystrophy locus is close to the centromere.     

Measurement of the Elastic Modulus for Red Cell Membrane Using a Fluid Mechanical Technique

Red cells which adhere to a surface in a parallel plate flow channel are stretched when acted on by a fluid shear stress. Three types of stretching are studied: whole cell stretching, the stretching of a red cell evagination, and tether (long, thin membrane process) stretching. In addition, the stretching of a large scale model cell attached to a surface is studied in a Couette flow channel. The results indicate that the uniaxial stretching of red cell membrane can be described by a linear stress-strain relationship. Simple theories developed from free body diagrams permit the calculation of a value for the modulus of elasticity of cell membrane in each of the three experiments. In all cases the value for the modulus is on the order of 10⁴ dyn/cm² for an assumed membrane thickness of 0.01 μm. It was also observed that red cell tethers steadily increase in length when the fluid shear stress is greater than approximately 1.5 dyn/cm² and tether lengths in excess of 200 μm have been achieved. Tethers appear to possess both fluid and elastic properties.