[Increasing pigmentation in Schmidt syndrome (polyglandular autoimmune syndrome type II]. / Pigmentvermehrung bei Schmidt-Syndrom (polyglanduläres Autoimmunsyndrom Typ II).

An 18-year old man presented with increasing pigmentation in multiple nevi as well as so-called "eruptive nevi" over a 24 month period. The first excisional biopsy was from a plantar nevus which showed melanocytic hyperplasia. Following excisions of both hyperpigmented and newly appearing nevi showed only increased pigmentation. Two years after the first examination Addison-like hyperpigmentation was noticed in typical locations. Both Addison disease and Hashimoto thyroiditis were then confirmed by elevated serum levels of ACTH, TSH, and decreased levels of cortisol and L-thyroxine. This confirmed the diagnosis of Schmidt syndrome as part of polyglandular autoimmune disease (PGAS) type II. After another 18 months of treatment with hormone substitution of L-thyroxine and hydrocortisone, the hyperpigmentation resolved and the hyperpigmented nevi decreased in number.

copia-, gypsy- and LINE-like retrotransposon fragments in the mitochondrial genome of Arabidopsis thaliana.

Several retrotransposon fragments are integrated in the mitochondrial genome of Arabidopsis thaliana. These insertions are derived from all three classes of nuclear retrotransposons, the Ty1/copia-, Ty3/gypsy- and non-LTR/LINE-families. Members of the Ty3/gypsy group of elements have not yet been identified in the nuclear genome of Arabidopsis. The varying degrees of similarity with nuclear elements and the dispersed locations of the sequences in the mitochondrial genome suggest numerous independent transfer-insertion events in the evolutionary history of this plant mitochondrial genome. Overall, we estimate remnants of retrotransposons to cover > or = 5% of the mitochondrial genome in Arabidopsis.

RNA editing of a conserved reading frame in plant mitochondria increases its similarity to two overlapping reading frames in Escherichia coli.

An open reading frame (orfx) in mitochondria of the higher plants Oenothera berteriana and Arabidopsis thaliana is homologous to orf244 in the mitochondrial genome of Marchantia polymorpha. Homologous sequences are also present in carrot, potato and sugar beet. Profile analysis revealed similarity to two overlapping reading frames in the Escherichia coli genome. Potential translation initiation at conserved ATA (isoleucine) and TTG (leucine) codons is discussed. Transcripts of the open reading frame are altered by RNA editing in Arabidopsis and Oenothera downstream of these codons, suggesting this to be the functionally important region.

The nad4L gene is encoded between exon c of nad5 and orf25 in the Arabidopsis mitochondrial genome.

In the Arabidopsis thaliana mitochondrial genome the gene coding for subunit 4L of NADH dehydrogenase (nad4L) is located between exon c of the nad5 open reading frame and orf25. The physical proximity of these genes further supports the trans-splicing model for assembly of the nad5 mRNA. Some transcripts comprise the nad4L open reading frame cotranscribed with nad5 exon c and orf25, while other mRNAs contain only nad4L and orf25. Both open reading frames for nad4L and orf25 are edited in several positions with different frequencies.