The productive gene for alpha-H chain disease protein MAL is highly modified by insertion-deletion processes.

alpha-H chain diseases (HCD) is a human lymphoproliferative disorder, characterized by the production of truncated alpha-Ig H chains, without associated L chains. In this study, we have analysed the serum protein, the alpha-HCD mRNA and the rearranged alpha-HCD gene from the leukemic cells of a patient (MAL) with alpha-HCD. The abnormal MAL serum Ig consisted of short alpha 1-chains, lacking VH and CH1 domains (only CH2 and CH3 domains were present).

Genomic alterations in a case of alpha heavy chain disease leading to the generation of composite exons from the JH region.

Human alpha heavy chain disease (HCD) is characterized by the presence in patient's serum of a short Ig alpha chain devoid of light chains. We analyzed the serum protein, the alpha HCD mRNA and the productive rearranged H chain gene from the leukemic cells of a new case (YAO) of alpha HCD. The abnormal YAO alpha 1 Ig was devoid of VH and CH1 domains and started at the beginning of the hinge region.

Characterization of interleukin-2 receptors expressed on acute leukemic B cells.

More than 90% of both unfractionated and blast-enriched T cell-depleted mononuclear cells (MNC) from a patient with a morphologically and phenotypically unclassified acute leukemia expressed interleukin 2 receptors (IL2-R), whereas 50% unfractionated MNC displayed monocyte/myeloid- (My7, My9, and OKM1) and B cell-restricted (B4) antigens. Two-color fluorescence studies showed that 80% of the My9+ cells expressed the B4 antigen and 63% of the B4+ cells were IL2-R+. Cell incubation with phorbol myristate acetate (PMA) increased the expression of B4 antigen and significantly decreased the proportion of My9+ and IL2-R-bearing cells.

Complete mRNA coding sequence of the acetylcholine binding alpha-subunit of Torpedo marmorata acetylcholine receptor: a model for the transmembrane organization of the polypeptide chain.

A 1,350-base-pair-long cDNA clone, named p alpha-2, was isolated by hybridization to the previously characterized clone p alpha-1 and found to be specific for the alpha-subunit of the Torpedo marmorata acetylcholine receptor. The nucleotide sequences of both cDNA inserts were analyzed and the sequence of the complete coding region and part of the 5' and 3' untranslated regions of the alpha-chain mRNA was determined. The complete amino acid sequence of the alpha-chain precursor is presented and used to develop a model for the transmembrane organization of the polypeptide.

Dependence on pH of parameters of lactose transport in Escherichia coli. Evidence for an essential protonated group of the carrier.

The kinetic parameters Km and V of transported by the lactose permease of Escherichia coli have been explored in the pH range 4.8--9.2.

Artificially induced active transport of amino acid driven by the efflux of a sugar via a heterologous transport system in de-energized Escherichia coli.

Consistent with the model of an H+ cotransport, amino acid uptake can be driven by a proton gradient generated by an efflux of sugar when the normal energy sources are suppressed. Heterologous countertransport is completely inhibited by uncouplers unlike homologous countertransport. Positive coupling was obtained with methyl thiogalactoside/proline, methyl thiogalactoside/phenylalanine, gluconate/proline; however, the poor coupling efficiency suggests a more complex sequence of reactions.

Counter-transport mediated by the lactose permease of Escherichia coli.

When the two main energy yielding pathways, respiration and the membrane ATPase of Escherichia coli are poisoned, the lactose permease is unable to accomplish accumulative transport of thiogalactosides, but the efflux of preloaded substrate can be coupled to a transiently uphill transport of exogenous substrate. This transient uphill transport, called overshoot has been reexamined with the possibility of an obligate H+ cotransport in mind. Overshoot can be diminished but not suppressed by a proton-conducting uncoupler, carbonyl cyanide m chlorophenylhydrazone, (CCCP) and by a liposoluble cation, triphenyl-methyl phosphonium (TPMP+).