Shy1p occurs in a high molecular weight complex and is required for efficient assembly of cytochrome c
 oxidase in yeast

To identify essential molecules capable of inducing terminal morphologic maturation and cell death of myeloid progenitor cells, we isolated cDNA clones by functional expression cloning using a library constructed from all-trans retinoic acid (ATRA)-treated human promyelocytic HL-60 cells. Clones which induced morphologic changes in HL-60 cells from blastic cells to mature neutrophilic granulocytes were selected. The isolated positive cDNA clone was demonstrated to encode an antisense RNA for cytochrome c oxidase/serine tRNA derived from a mitochondrial gene (MARCO). When MARCO was expressed in HL-60 cells with the lac switch system, blastic cell morphology became neutrophilic after 48-hour incubation with IPTG, and cell death was observed after 3 days. Also, high molecular weight DNA fragmentation was observed after 36 hours in culture. Similar results were observed using transformants from human K562 cells and CMK cells. RT-PCR analysis revealed that MARCO was transcribed in both ATRA and TNF-α systems, and also in human blood neutrophilic granulocytes. Following transfection with cytochrome c oxidase expression plasmids, TNF-α–induced high molecular weight DNA fragmentation in U937 cells and HL-60 cells was inhibited in these transformants. These results indicate that maturational changes in hematopoietic cells and the process of cell death may be induced by mitochondrial respiratory insufficiency, and also that the mitochondrial gene MARCO may be used as one of the candidates for gene supplementation therapy for the acute leukemias.

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High molecular weight complex of tyrosyl-tRNA synthetase from bovine liver

Biopolymers and Cell ◽

10.7124/bc.0002b3 ◽

1991 ◽

Vol 7 (1) ◽

pp. 63-69 ◽

Cited By ~ 6

Author(s):

D. V. Gnatenko ◽

A. I. Kornelyuk ◽

I. V. Kurochkin ◽

G. H. Matsuka

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Bovine Liver ◽

Trna Synthetase ◽

High Molecular Weight Complex

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The 70-kilodalton adenylyl cyclase-associated protein is not essential for interaction of Saccharomyces cerevisiae adenylyl cyclase with RAS proteins

Molecular and Cellular Biology ◽

10.1128/mcb.12.11.4937-4945.1992 ◽

1992 ◽

Vol 12 (11) ◽

pp. 4937-4945

Author(s):

J Wang ◽

N Suzuki ◽

T Kataoka

Keyword(s):

Saccharomyces Cerevisiae ◽

Molecular Weight ◽

Adenylyl Cyclase ◽

High Molecular Weight ◽

Size Difference ◽

Missense Mutations ◽

Ras Proteins ◽

High Molecular Weight Complex ◽

Ras Protein ◽

Dependent Activity

In the yeast Saccharomyces cerevisiae, adenylyl cyclase is regulated by RAS proteins. We show here that the yeast adenylyl cyclase forms at least two high-molecular-weight complexes, one with the RAS protein-dependent adenylyl cyclase activity and the other with the Mn(2+)-dependent activity, which are separable by their size difference. The 70-kDa adenylyl cyclase-associated protein (CAP) existed in the former complex but not in the latter. Missense mutations in conserved motifs of the leucine-rich repeats of the catalytic subunit of adenylyl cyclase abolished the RAS-dependent activity, which was accompanied by formation of a very high molecular weight complex having the Mn(2+)-dependent activity. Contrary to previous results, disruption of the gene encoding CAP did not alter the extent of RAS protein-dependent activation of adenylyl cyclase, while a concomitant decrease in the size of the RAS-responsive complex was observed. These results indicate that CAP is not essential for interaction of the yeast adenylyl cyclase with RAS proteins even though it is an inherent component of the RAS-responsive adenylyl cyclase complex.

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