Disease relevance of LONP1

• A truncated LON gene, in which translation was initiated at Met118 of the coding sequence, was expressed in Escherichia coli and produced a protease that degraded alpha-casein in vitro in an ATP-dependent manner and had other properties similar to E. coli Lon protease [1].
• The response of a human embryonal carcinoma cell line LICR LON HT39/7 to 12-O-tetradecanylphorbol 13-acetate (TPA) has been studied [2].
• Biochemical and physiochemical characteristics of a pre-B cell stimulating factor produced by the plasmacytoma cell line LICR LON HMY2 [3].

High impact information on LONP1

• Two of the cell lines, LICR LON HT 39/7 and Tera 1, did not synthesize fibronectin, whereas all the other cell lines did [4].
• The primary product of transcription and translation directed by a human LON cDNA in vitro had an apparent mass of approximately 107 kDa, and incubation of the translation product with isolated rat liver mitochondria converted the precursor into the approximately 100-kDa mature form [5].
• The alterations in the phenotype of LICR LON HT39/7 induced by TPA are irreversible and the altered cells, whilst they stop dividing, can be maintained for at least three weeks in culture [2].
• In Escherichia coli, LON is known to regulate gene expression by targeting specific regulatory proteins for degradation [6].
• These findings suggest that the human LON protease might regulate mitochondrial DNA replication and/or gene expression using site-specific, single-stranded DNA binding to target the degradation of regulatory proteins binding to adjacent sites in mitochondrial promoters [6].

Biological context of LONP1

• In yeast, LON has been shown to be essential for the maintenance of the integrity of the mitochondrial genome [6].
• Overlapping cDNA clones containing mRNA for a putative Lon protease (LonHS) were isolated from cDNA libraries prepared from human brain poly(A)+ RNA [7].
• The results showed that (a) the seasonal activities started in April and ended by the end of November, with a well marked bimodal distribution in one year, (b) the sex ratio (male to female) 1:2.9 (c) 0.14% of 4208 females were naturally infected with promastigotes and typing proved to be Leishmania major, zymodeme LON 70 [8].

Anatomical context of LONP1

• Northern blot analysis revealed LonHS mRNA in lung, duodenum, liver and heart, but not in thymus cells [7].
• Monoclonal antibodies were raised against the human germ-cell tumor line, LICR LON HT39/7 [9].
• The molecules of the human milk fat globule membrane (MFGM) which bind four murine monoclonal antibodies (LICR LON M3, M8, M18 and M24) raised against the human MFGM have been identified [10].
• Monoclonal antibody LICR LON/FIB86 is cytotoxic for human fibroblasts from at least some sources, with rabbit complement [11].

Associations of LONP1 with chemical compounds

• Residues of the 'A' and 'B' motifs of NTP-binding pattern and a plausible catalytic serine residue are conserved in LonHS [7].
• One of these antibodies, LICR LON FC 10.2, has been found to react with a membrane glycoprotein of molecular weight 200,000 restricted in distribution to the surfaces of undifferentiated teratoma-derived cell lines, the luminal surface of human fetal intestine and bronchus and areas of putative endodermal differentiation within germ-cell neoplasms [9].
• Injections of depot methylprednisolone into the region of the GON and LON produced complete relief of headache in 169 out of 180 patients with CEH for a period ranging from 10 to 77 days, the mean duration of relief being 23.5 days [12].

References