Infantile neuroaxonal dystrophy (INAD) is an autosomal recessive progressive neurodegenerative disease that presents within the first 2 years of life and culminates in death by age 10 years. Affected individuals from two unrelated Bedouin Israeli kindreds were studied. Brain imaging demonstrated diffuse cerebellar atrophy and abnormal iron deposition in the medial and lateral globus pallidum. Progressive white-matter disease and reduction of the N-acetyl aspartate : chromium ratio were evident on magnetic resonance spectroscopy, suggesting loss of myelination. The clinical and radiological diagnosis of INAD was verified by sural nerve biopsy. The disease gene was mapped to a 1.17-Mb locus on chromosome 22q13.1 (LOD score 4.7 at recombination fraction 0 for SNP rs139897), and an underlying mutation common to both affected families was identified in PLA2G6, the gene encoding phospholipase A2 group VI (cytosolic, calcium-independent). These findings highlight a role of phospholipase in neurodegenerative disorders.

Proto-oncogene fos encodes a nuclear phosphoprotein of 380 amino acids that can modulate the transcription of other genes either by transactivation or by transrepression. The v-Fos protein (381 amino acids) shares the first 332 amino acids with the c-Fos protein (with five single amino-acid changes), but differs at the C terminus. We have previously reported that the c-Fos protein undergoes more extensive post-translational modification than v-Fos (refs 9, 10). The major modification of the c-Fos protein involves serine phosphoesterification of sites in the extreme C terminus. We therefore argued that modification of the C-terminal region of the c-Fos protein may be involved in its ability to transrepress transcription without compromising its ability to transactivate other genes. Here we show that mutant c-Fos protein which is hypophosphorylated at its C terminus is unable to repress transcription of the c-fos promoter following induction with serum or tetraphorbol acetate. The C-terminal phosphorylation-deficient mutant is, however, fully competent to activate transcription of promoters containing a phorbol response element. The requirement for phosphorylation can be offset by the introduction of a net negative charge in the C terminus of the Fos protein.

We describe a maternally transmitted genomic-imprinting syndrome of mental retardation, hypotonia, and unique dysmorphism with elongated face. We mapped the disease-associated locus to approximately 7.27 Mb on chromosome 8q24 and demonstrated that the disease is caused by a missense mutation in the maternal copy of KCNK9 within this locus. KCNK9 is maternally transmitted (imprinted with paternal silencing) and encodes K(2P)9.1, a member of the two pore-domain potassium channel (K(2P)) subfamily. The mutation fully abolishes the channel's currents--both when functioning as a homodimer or as a heterodimer with K(2P)3.1.

The essential micronutrient selenium is found in proteins as selenocysteine (Sec), the only genetically encoded amino acid whose biosynthesis occurs on its cognate tRNA in humans. In the final step of selenocysteine formation, the essential enzyme SepSecS catalyzes the conversion of Sep-tRNA to Sec-tRNA. We demonstrate that SepSecS mutations cause autosomal-recessive progressive cerebellocerebral atrophy (PCCA) in Jews of Iraqi and Moroccan ancestry. Both founder mutations, common in these two populations, disrupt the sole route to the biosynthesis of the 21st amino acid, Sec, and thus to the generation of selenoproteins in humans.

Citral, 3,7-dimethyl-2,6-octadien-1-al, a key component of the lemon-scented essential oils extracted from several herbal plants such as lemon grass (Cymbopogon citratus), melissa (Melissa officinalis), verbena (Verbena officinalis) is used as a food additive and as a fragrance in cosmetics. In this study, we investigated the anti-cancer potential of citral and its mode of action. Concentrations of 44.5 muM, comparable to the concentration of citral in a cup of tea prepared from 1 g of lemon grass, induced apoptosis in several hematopoietic cancer cell lines. Apoptosis was accompanied by DNA fragmentation and caspase-3 catalytic activity induction. Citral activity (22.25 microM) was compared to a reference compound like staurosporine (0.7 microM), in respect to DNA fragmentation and caspase-3 enzymatic activity. The apoptotic effect of citral depended on the alpha,beta-unsaturated aldehyde group.