Isolation of a sequence encoding human cystatin C. Conservation of exon-intron structure between members of the cysteine proteinase inhibitors superfamily.

The human cystatin C gene was cloned using a synthetic oligonucleotide predicted from a portion of its amino-acid sequence. The nucleotide sequence of the restriction fragment hybridizing with the oligonucleotide confirms the existence of one exon encoding amino acids 56-93 of human cystatin C and its relationship to kininogens. However the deduced amino-acid sequence differs in one position from the sequence of the cystatin C fragment deposited as amyloid fibrils in hereditary cerebral hemorrhage with amyloidosis of icelandic origin.

Coronary angioplasty in pregnancy.

Myocardial infarction is rare in pregnancy. A 30 year old white primigravida had an anterior infarct at 20 weeks' gestation, which was followed by troublesome angina. Coronary angiography showed a tight stenosis of the left anterior descending coronary artery.

The primary structure and heterogeneity of tau protein from mouse brain.

Tau protein is a family of microtubule binding proteins, heterogeneous in molecular weight, that are induced during neurite outgrowth and are found prominently in neurofibrillary tangles in Alzheimer's disease. The predicted amino acid sequences of two forms of tau protein from mouse brain were determined from complementary DNA clones. These forms are identical in their amino-terminal sequences but differ in their carboxyl-terminal domains.

Structure and evolutionary origin of the gene encoding mouse NF-M, the middle-molecular-mass neurofilament protein.

We describe the complete sequence of the gene encoding mouse NF-M, the middle-molecular-mass neurofilament protein. The coding sequence is interrupted by two intervening sequences which align perfectly with the first two intervening sequences in the gene encoding NF-L (the low-molecular-mass neurofilament protein); there is no intron in the gene encoding NF-M corresponding to the third intron in NF-L. Therefore, both the number of introns and their arrangement in the genes coding NF-L and NF-M contrast sharply with the number and arrangement of introns in the genes of known sequence, encoding other members of the intermediate filament multigene family (desmin, vimentin, glial fibrillary acidic protein and the acidic and basic keratins); with the exception of a single truncated keratin gene that lacks an encoded tailpiece, these genes all contain eight introns, of which at least six are placed at homologous locations.

Free intermingling of mammalian beta-tubulin isotypes among functionally distinct microtubules.

Mammalian cells express a spectrum of tubulin isotypes whose relationship to the diversity of microtubule function is unknown. To examine whether different isotypes are segregated into functionally distinct microtubules, we generated immune sera capable of discriminating among the various naturally occurring beta-tubulin isotypes. Cloned fusion proteins encoding each isotype were used first to tolerogenize animals against shared epitopes, and then as immunogens to elicit a specific response.

Neurofilament gene expression: a major determinant of axonal caliber.

Within the wide spectrum of axonal diameters occurring in mammalian nerve fibers, each class of neurons has a relatively restricted range of axonal calibers. The control of caliber has functional significance because diameter is the principal determinant of conduction velocity in myelinated nerve fibers. Previous observations support the hypothesis that neurofilaments (NF) are major intrinsic determinants of axonal caliber in large myelinated nerve fibers.

Auditory sensory storage in relation to the growth of sensation and acoustic information extraction.

A brief, vivid phase of auditory sensory storage that outlasts the stimulus could be used in perception in two ways: First, all of the neural activity resulting from the stimulus, including that of the sensory store, could contribute to a sensation of growing loudness; second, the sensory store could permit the continued extraction of information about the sound's acoustic properties. This study includes a task for which these two processes lead to different predictions; a third prediction is based on the two processes combined. The task required loudness judgments for two brief tones presented with a variable intertone interval.

The mammalian beta-tubulin repertoire: hematopoietic expression of a novel, heterologous beta-tubulin isotype.

We describe the structure of a novel and unusually heterologous beta-tubulin isotype (M beta 1) isolated from a mouse bone marrow cDNA library, and a second isotype (M beta 3) isolated from a mouse testis cDNA library. Comparison of M beta 1 and M beta 3 with the completed (M beta 4, M beta 5) or extended (M beta 2) sequence of three previously described beta-tubulin isotypes shows that each includes a distinctive carboxy-terminal region, in addition to multiple amino acid substitutions throughout the polypeptide chain. In every case where a mammalian interspecies comparison can be made, both the carboxy-terminal and internal amino acid substitutions that distinguish one isotype from another are absolutely conserved.

Six mouse alpha-tubulin mRNAs encode five distinct isotypes: testis-specific expression of two sister genes.

Five mouse alpha-tubulin isotypes are described, each distinguished by the presence of unique amino acid substitutions within the coding region. Most, though not all of these isotype-specific amino acids, are clustered at the carboxy terminus. One of the alpha-tubulin isotypes described is expressed exclusively in testis and is encoded by two closely related genes (M alpha 3 and M alpha 7) which have homologous 3' untranslated regions but which differ at multiple third codon positions and in their 5' untranslated regions.

A cloned cDNA encoding MAP1 detects a single copy gene in mouse and a brain-abundant RNA whose level decreases during development.

Screening of a bacteriophage lambda gt11 cDNA expression library with a polyclonal anti-microtubule associated protein (MAP) antiserum resulted in the isolation of two non-cross-hybridizing sets of cDNA clones. One set was shown to encode MAP2 (Lewis, S. A.

Brain-specific expression of MAP2 detected using a cloned cDNA probe.

We describe the isolation of a set of overlapping cDNAs encoding mouse microtubule associated protein 2 (MAP2), using an anti-MAP antiserum to screen a mouse brain cDNA expression library cloned in bacteriophage lambda gt11. The authenticity of these clones was established by the following criteria: (a) three non-identical clones each expressing a MAP2 immunoreactive fusion protein were independently isolated from the expression library; each of these clones cross-hybridized at the nucleic acid level; (b) anti-MAP antiserum was affinity purified using nitrocellulose-bound fusion protein; these antibodies detected only MAP2 in an immunoblot experiment of whole brain microtubule protein; (c) a series of cDNA "walking" experiments was done so as to obtain a non-overlapping cloned fragment corresponding to a different part of the same mRNA molecule. Upon subcloning this non-overlapping fragment into plasmid expression vectors, a fusion protein was synthesized that was immunoreactive with an anti-MAP2 specific antiserum.

Anomalous placement of introns in a member of the intermediate filament multigene family: an evolutionary conundrum.

The origin of introns and their role (if any) in gene expression, in the evolution of the genome, and in the generation of new expressed sequences are issues that are understood poorly, if at all. Multigene families provide a favorable opportunity for examining the evolutionary history of introns because it is possible to identify changes in intron placement and content since the divergence of family members from a common ancestral sequence. Here we report the complete sequence of the gene encoding the 68-kilodalton (kDa) neurofilament protein; the gene is a member of the intermediate filament multigene family that diverged over 600 million years ago.

Tubulin pseudogenes as markers for hominoid divergence.

Processed pseudogenes arise via unimolecular events that result in the integration of nonfunctional (and therefore non-selected) regions of DNA into the germ line. The sequence of such pseudogenes can be used as a novel form of evolutionary clock: the older a particular pseudogene, the more mutations it has acquired relative to the selectively constrained functional gene from which it was originally derived. We have used specific beta-tubulin gene probes to assay for the presence of fully sequenced processed pseudogenes in genomic DNA from various hominoid species.

The use of auditory and phonetic memory in vowel discrimination.

A commonly held assumption about memory for speech is that auditory memory is referred to only if phonetic memory does not contain the information needed for a particular trial. However, this assumption is in conflict with recent evidence [Crowder, J. Exp.

Five mouse tubulin isotypes and their regulated expression during development.

We describe five mouse tubulin cloned cDNAs, two (M alpha 1 and M alpha 2) that encode alpha-tubulin and three (M beta 2, M beta 4, and M beta 5) that encode beta-tubulin. The sequence of these clones reveals that each represents a distinct gene product. Within the sequence common to the two alpha-tubulin cDNAs, the encoded amino acids are identical, though the 3' noncoding regions are wholly dissimilar.

Temporal expression of mouse glial fibrillary acidic protein mRNA studied by a rapid in situ hybridization procedure.

A rapid and sensitive in situ hybridization technique is described for the detection of mRNA sequences in 6-8-micron cryostat sections. The method incorporates the use of alpha-thio-35S-labelled nucleoside triphosphates for the generation of high-specific-activity DNA probes and a high-stringency washing procedure that virtually eliminates background without unduly compromising histological integrity. Whereas signal resolution is less than that observed using 3H probes, 35S-labelled probes are well-suited for experiments where resolution at the cellular level is required.

Structure of the mouse glial fibrillary acidic protein gene: implications for the evolution of the intermediate filament multigene family.

We report the complete sequence of the gene encoding mouse glial fibrillary acidic protein (GFAP), the intermediate filament (IF) protein specific to astrocytes. The 9.8 kb gene includes nine exons separated by introns ranging in size from 0.

Three expressed sequences within the human beta-tubulin multigene family each define a distinct isotype.

This paper describes the isolation and complete sequence of a novel expressed human beta-tubulin gene (beta 2). The sequence is compared with that of two other expressed human beta-tubulin genes (M40 and 5 beta). All are encoded by four exons.

Genetics, evolution, and expression of the 68,000-mol-wt neurofilament protein: isolation of a cloned cDNA probe.

A 1.2-kilobase (kb) cDNA clone (NF68) encoding the mouse 68,000-mol-wt neurofilament protein is described. The clone was isolated from a mouse brain cDNA library by low-stringency cross-hybridization with a cDNA probe encoding mouse glial fibrillary acidic protein (Lewis et al.

Structural features and restricted expression of a human alpha-tubulin gene.

The nucleotide sequence of a human alpha-tubulin gene (b alpha 1) is described. This gene is extensively homologous to a rat alpha-tubulin gene in its coding regions, 3'-untranslated region and, indeed, in segments of its largest intron. However, with the exception of three short conserved blocks of homology, the 5' flanking regions of the rat and human genes are unrelated.