Search

Your search keyword '"Bongiorni, S"' showing total 3 results
Start Over Author "Bongiorni, S" Journal journal of cell science
3 results on '"Bongiorni, S"'

2. Epigenetic regulation of facultative heterochromatinisation in Planococcus citri via the Me(3)K9H3-HP1-Me(3)K20H4 pathway.

Author

Bongiorni S, Pasqualini B, Taranta M, Singh PB, and Prantera G

Subjects
Animals, Chromosome Aberrations, Embryo, Nonmammalian physiology, Genomic Imprinting, Hemiptera genetics, Histones chemistry, Insect Proteins genetics, Lysine chemistry, Male, Methylation, Nuclear Proteins genetics, RNA, Double-Stranded metabolism, Signal Transduction, Epigenesis, Genetic, Hemiptera physiology, Heterochromatin physiology, Histones physiology, Insect Proteins physiology, Metaphase physiology, Nuclear Proteins physiology
Abstract

Using RNA interference (RNAi) we have conducted a functional analysis of the HP1-like chromobox gene pchet2 during embryogenesis of the mealybug Planococcus citri. Knocking down pchet2 expression results in decondensation of the male-specific chromocenter that normally arises from the developmentally-regulated facultative heterochromatinisation of the paternal chromosome complement. Together with the disappearance of the chromocenter the staining levels of two associated histone modifications, tri-methylated lysine 9 of histone H3 [Me(3)K9H3] and tri-methylated lysine 20 of histone H4 [Me(3)K20H4], are reduced to undetectable levels. Embryos treated with double-stranded RNA (dsRNA) targeting pchet2 also exhibit chromosome abnormalities, such as aberrant chromosome condensation, and also the presence of metaphases that contain 'lagging' chromosomes. We conclude that PCHET2 regulates chromosome behavior during metaphase and is a crucial component of a Me(3)K9H3-HP1-Me(3)K20H4 pathway involved in the facultative heterochromatinisation of the (imprinted) paternal chromosome set. more...

Published
2007
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results

3. Heterochromatin and tri-methylated lysine 20 of histone H4 in animals.

Author

Kourmouli N, Jeppesen P, Mahadevhaiah S, Burgoyne P, Wu R, Gilbert DM, Bongiorni S, Prantera G, Fanti L, Pimpinelli S, Shi W, Fundele R, and Singh PB

Subjects
Animals, Cell Line, Cell Nucleus metabolism, Cells, Cultured, Centromere chemistry, Chromosomes metabolism, Culture Media, Serum-Free, DNA biosynthesis, Drosophila genetics, Drosophila metabolism, Embryo, Mammalian metabolism, Embryo, Nonmammalian, Female, Fibroblasts metabolism, Fluorescent Antibody Technique, Indirect, Genetic Markers, Hemiptera metabolism, Male, Methylation, Mice embryology, Microscopy, Fluorescence, Oocytes metabolism, S Phase, Spermatozoa metabolism, Telomere metabolism, Heterochromatin metabolism, Histones metabolism, Lysine metabolism
Abstract

Tri-methylated lysine 20 on histone H4 (Me(3)K20H4) is a marker of constitutive heterochromatin in murine interphase and metaphase cells. Heterochromatin marked by Me(3)K20H4 replicates late during S phase of the cell cycle. Serum starvation increases the number of cells that exhibit high levels of Me(3)K20H4 at constitutive heterochromatin. Me(3)K20H4 is also present at the centromeric heterochromatin of most meiotic chromosomes during spermatogenesis and at the pseudoautosomal region, as well as at some telomeres. It is not present on the XY-body. During murine embryogenesis the maternal pronucleus contains Me(3)K20H4; Me(3)K20H4 is absent from the paternal pronucleus. On Drosophila polytene chromosomes Me(3)K20H4 is present in a 'punctate pattern' at many chromosomal bands, including the chromocenter. In coccids it is present on the facultatively heterochromatinised paternal chromosome set. We also present evidence that Me(3)K20H4 is dependent upon H3-specific Suv(3)9 histone methyltransferase activity, suggesting that there may be 'epigenetic cross-talk' between histones H3 and H4. more...

Published
2004
Full Text
View/download PDF