Drosophila nuclear lamin precursor Dm0 is translated from either of two developmentally regulated mRNA species apparently encoded by a single gene.

A cDNA clone encoding a portion of Drosophila nuclear lamins Dm1 and Dm2 has been identified by screening a lambda-gt11 cDNA expression library using Drosophila lamin-specific monoclonal antibodies. Two different developmentally regulated mRNA species were identified by Northern blot analysis using the initial cDNA as a probe, and full-length cDNA clones, apparently corresponding to each message, have been isolated. In vitro transcription of both full-length cDNA clones in a pT7 transcription vector followed by in vitro translation in wheat germ lysate suggests that both clones encode lamin Dm0, the polypeptide precursor of lamins Dm1 and Dm2. Nucleotide sequence analyses confirm the impression that both cDNA clones code for the identical polypeptide, which is highly homologous with human lamins A and C as well as with mammalian intermediate filament proteins. The two clones differ in their 3'-untranslated regions. In situ hybridization of lamin cDNA clones to Drosophila polytene chromosomes shows only a single locus of hybridization at or near position 25F on the left arm of chromosome 2. Southern blot analyses of genomic DNA are consistent with the notion that a single or only a few highly similar genes encoding Drosophila nuclear lamin Dm0 exist in the genome

Primary structure and functional expression of a cyclic nucleotidegated channel from rabbit aorta

Sequences specific for cyclic nucleotide-gated channels (CNG channels) have been amplified by PCR from cDNA of heart, aorta, sinoatrial node, cerebellum, C-cells and kidney. The complete amino acid sequence of a CNG channel from rabbit aorta has been deduced by cloning and sequence analysis of the cDNA. Synthetic RNA derived from this cDNA induces the formation of a functional CNG channel in Xenopus oocytes

Molecular cloning and sequence analysis of the cDNA encoding the human acrosin-trypsin inhibitor (HUSI-II)

A complete cDNA clone encoding the human acrosin-trypsin inhibitor HUSI-II has been isolated from a cDNA library of human testis and completely sequenced. The cDNA of 594 bp contained an open reading frame of 252 base pairs, The deduced amino acid sequence comprised the complete amino acid sequence of HUSI-II[1] and a putative signal peptide. Northern blotting analysis revealed that HUSI-II is synthesized in testis, epididymis and seminal vesicle, but not in the prostate gland

Cloning of terminal transferase cDNA by antibody screening

A cDNA library was prepared from a terminal deoxynucleotidyltransferase-containing thymoma in the phage vector λgt11. By screening plaques with anti-terminal transferase antibody, positive clones were identified of which some had β-galactosidase-cDNA fusion proteins identifiable after electrophoretic fractionation by immunoblotting with anti-terminal transferase antibody. The predominant class of cross-hybridizing clones was determined to represent cDNA for terminal transferase by showing that one representative clone hybridized to a 2200-nucleotide mRNA in close-matched enzyme-positive but not to enzyme-negative cells and that the cDNA selected a mRNA that translated to give a protein of the size and antigenic characteristics of terminal transferase. Only a small amount of genomic DNA hybridized to the longest available clone, indicating that the sequence is virtually unique in the mouse genome

Primary structure and functional expression of a high voltage activated calcium channel from rabbit lung

The complete amino acid sequence of the receptor for organic calcium channel blockers (CaCB) from rabbit lung has been deduced by cloning and sequence analysis of the cDNA. Synthetic RNA derived from this cDNA induces the formation of a functional CaCB-sensitive high voltage activated calcium channel in Xenopus oocytes

Human interleukin-1 receptor antagonist is expressed in liver

AbstractUsing PCR and Northern blot analysis, an IL-1 receptor antagonist specific transcript was amplified from HepG2- and liver mRNA, cDNA clones coding for IL-1 receptor antagonist were isolated from a liver cDNA library and sequence comparison revealed complete identity with the secreted, monocytic form of IL-1 receptor antagonist

Sequence of a putative human housekeeping gene (HK33) localized on chromosome 1

A gene (X33) localized on human chromosome 1 has been detected by crossreaction of its fusion protein with a monospecific antiserum directed against human vitamin-D-binding protein (hDBP; group-specific component). Its cDNA sequence analysis showed no evident homologies neither to the sequence encoding hDBP nor to any other sequence. The largest cDNA clone of 3.2 kb includes a 897-bp coding region and a large 3’ untranslated region with at least four polyadenylation sites. Further cDNA amplification using PCR demonstrated a total cDNA length of approx. 3.7 kb. Northern blot analysis revealed signals at about 2.2-2.5 kb and 4.0 kb, the shorter transcripts representing mRNAs using one of the two polyadenylation sites at about 2.0 kb. Synthesis of the 299-amino-acid polypeptide (33 kDa) in the bacterial host, with subsequent Western blot analysis, verified the sequence-specific recognition by the hDBPspecific antiserum. The search of protein databanks revealed no homology of HK33 to any known sequence. Since the gene is transcribed in all cells and tissues tested so far, it is a strong candidate for another housekeeping gene

cDNA that encodes active agrin

Agrin is thought to mediate the motor neuron-induced aggregation of AChRs and AChE on the surface of muscle fibers at neuromuscular junctions. We have isolated a cDNA from a chick brain library that, based on sequence homology and expression experiments, codes for active agrin. Examination of the sequence reveals considerable similarity to homologous cDNAs previously isolated from ray and rat libraries. A conspicuous difference is an insertion of 33 by in chick agrin cDNA, which endows the encoded protein with AChR/AChE aggregating activity. Homologous transcripts having the 33 by insertion were detected in the ray CNS, which indicates that an insertion of similar size is conserved in agrin in many, if not all, vertebrate species. Results of in situ hybridization studies and PCR experiments on mRNA isolated from motor neuron-enriched fractions of the spinal cord indicate that, consistent with the agrin hypothesis, motor neurons contain transcripts that code for active agrin