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A signal transduction pathway called the unfolded protein response is activated when increased levels of misfolded proteins or incorrectly assembled subunits accumulate in the endoplasmic reticulum (ER). The expression of several genes for ER-resident foldases and chaperones, as well as genes encoding proteins that are involved in functions associated with the secretory process, are induced by this pathway. This paper describes the cloning and characterisation of genes for two components of the pathway, ire1 and ptc2, from the filamentous fungus Trichoderma reesei ( Hypocrea jecorina). The data presented demonstrates that the T. reesei genes can complement Saccharomyces cerevisiae mutants that are deficient in the corresponding homologues. The T. reesei IREI protein has intrinsic kinase activity, as revealed by an in vitro autophosphorylation assay. Overexpression of ire1 in a T. reesei strain that expresses a foreign protein (laccase 1 from Phlebia radiata), results in up-regulation of the UPR pathway, as indicated by the increased expression levels of the known UPR target genes bip1 and pdi1. Splicing of the mRNA encoding the transcription factor HAC1 is also observed. Other genes encoding proteins from different parts of the secretory pathway also respond to ire1 overexpression.

The unfolded protein response (UPR) involves a complex signalling pathway in which the transcription factor HACA plays a central role. Here we report the cloning and characterisation of the hacA gene and its product from Aspergillus niger. ER (endoplasmic reticulum) stress results in the splicing of an unconventional 20-nt intron from the A. niger hacA mRNA, and is associated with truncation of the 5'-end of the hacA mRNA by 230 nt. In this study the UPR was triggered by over expressing tissue plasminogen activator (t-PA), and by treatment of mycelia with dithiothreitol (DTT) or tunicamycin. Overexpression of the processed form of hacA not only led to the up-regulation of bipA, cypB and pdiA —mimicking the UPR—but also led to the up-regulation of the hacA gene itself. In vitro binding assays confirmed that the HACA protein binds to the promoters of genes encoding ER-localised chaperones and foldases, and to the promoter of the hacA gene itself. Finally, a GFP-HACA fusion was shown to localise in the nucleus.

Dolichol phosphate mannose (DPM) synthase activity, which is required in N:-glycosylation, O-mannosylation, and glycosylphosphatidylinositol membrane anchoring of protein, has been postulated to regulate the Trichoderma reesei secretory pathway. We have cloned a T.reesei cDNA that encodes a 243 amino acid protein whose amino acid sequence shows 67% and 65% identity, respectively, to the Schizosaccharomyces pombe and human DPM synthases, and which lacks the COOH-terminal hydrophobic domain characteristic of the Saccharomyces cerevisiae class of synthase. The Trichoderma dpm1 (Trdpm1) gene complements a lethal null mutation in the S.pombe dpm1(+) gene, but neither restores viability of a S.cerevisiae dpm1-disruptant nor complements the temperature-sensitivity of the S. cerevisiae dpm1-6 mutant. The T.reesei DPM synthase is therefore a member of the "human" class of enzyme. Overexpression of Trdpm1 in a dpm1(+)::his7/dpm1(+) S.pombe diploid resulted in a 4-fold increase in specific DPM synthase activity. However, neither the wild type T. reesei DPM synthase, nor a chimera consisting of this protein and the hydrophobic COOH terminus of the S.cerevisiae DPM synthase, complemented an S.cerevisiae dpm1 null mutant or gave active enzyme when expressed in E.coli. The level of the Trdpm1 mRNA in T.reesei QM9414 strain was dependent on the composition of the culture medium. Expression levels of Trdpm1 were directly correlated with the protein secretory capacity of the fungus.

The immunologic status of 59 patients with lung carcinoma was determined by analysis of peripheral venous blood samples. The following tests were performed: total leucocyte and lymphocyte counts, the number of acid alpha-naphthyl acetate esterase (ANAE) positive cells (T-cells), and phytohaemagglutinin (PHA) and tuberculin (PPD) transformation tests. The patients were divided into three treatment groups: a surgery group (S), a radiation therapy group (R), and a combined cytostatic and radiation therapy group (C). A follow-up was carried out 4 to 6 months after treatment. The therapeutic measures, resection, irradiation, and chemotherapy, produced a decrease in the total leucocyte and lymphocyte counts, in the number of T-cells, and in the leucocyte transformation response to PPD. In the surgically treated group the decrease was transient. In the groups treated with radiation therapy and combined cytostatic and radiation therapy the values remained low throughout the follow-up. The lymphocyte response to PHA was not altered in any of the groups during initial treatment. or follow-up. The results did not suggest a correlation between the immunologic parameters used and the stage and histologic type of lung cancer. The tests were of no clinical value in the determination of the individual prognosis.

The basidiomycete fungus Phanerochaete chrysosporiumproduces a number of extracellular peroxidases which appear to be important for lignin degradation. We present here the isolation and complete nucleotide (nt) sequence of a gene (Ipo)coding for lignin peroxidase (LPO), the coding region of which is identical to a IpocDNA sequence which had previously been described [M. Tien and C.-P.D. Tu, Nature 326 (1987) 520–523]. The deduced amino acid (aa) sequence corresponds to 372 aa residues and the coding region is interrupted by eight short introns that range m size from 50 to 62 nt. Southern blot experiments using the cloned Ipogene as a hybridization probe revealed a complex restriction fragment pattern, indicating that there are a number of lpo-rElated nucleotide sequences present m P. chrysosporiumDNA which cross-hybridize. We also present data on the in vivo expression of the Ipogenes and show that they are regulated at the RNA level and that the structure of the transcripts as judged from Sl experiments is complex. These data are consistent with the idea that there are a number of related Ipogenes in P. chrysosporiumwhich constitute a gene family.

Experiences based on over 500 bronchoscopies at Satakunta Sanatorium are reported. It is emphasized that bronchoscopy alone is not sufficient for a complete bronchial evaluation because its field is limited to the main and lobar bronchi and segmental orifices.