J Starling

Bio: J Starling is an academic researcher. The author has contributed to research in topics: Oligonucleotide & Satellite DNA. The author has an hindex of 1, co-authored 1 publications receiving 99 citations.

Oligonucleotide-primed in situ DNA synthesis (PRINS): a method for chromosome mapping, banding, and investigation of sequence organization.

Abstract: Oligonucleotides were annealed to complementary sequences in fixed human metaphase chromosomes and extended with DNA polymerase. The newly synthesized fragments were labeled by incorporating bio-11-dU

Chromosome abnormalities and their relationship to morphology and development of human embryos

Abstract: This review covers the relationship between chromosome abnormalities, morphological abnormalities and embryonic development. The baseline of chromosome abnormalities in human embryos produced by assisted reproduction is higher than 50%, regardless of maternal age. While aneuploidy increases with maternal age, abnormalities arising post-meiotically, such as mosaicism, chaoticism, polyploidy and haploidy, have similar incidence in all age groups (about 33%). Post-meiotic abnormalities do increase with dysmorphism. The most common dysmorphisms found in cleavage-stage embryos are multinucleation, fragmentation and uneven cells, among others. All dysmorphisms are associated with an increase in post-meiotic chromosome abnormalities and a decreased implantation potential. Similarly, embryos developing slowly or with arrested development have higher incidence of post-meiotic abnormalities than normally developing ones. Chromosome studies in blastocysts indicate that mosaicism is the most common abnormality but that the load of abnormal cells decreases with increasing blastocyst quality. Regardless of blastocyst quality, more than 40% of mosaics are still chromosomally abnormal and will not implant or will spontaneously abort. Because aneuploidy is not related to cleavage stage dysmorphism and trisomies can reach blastocyst stage and beyond, morphological analysis is not enough to select against chromosome abnormalities, and thus preimplantation genetic diagnosis should be recommended in patients 35 and older.

Nonradioactive labeling and detection of biomolecules

Abstract: This study gathers together all of the important nonradioactive labelling techniques for nucleic acids, proteins, glycoproteins and glycolipids like DIG, Biotin, BrdU, Sulfone, Immunogold, Silver Enhancement and SNAP, as well as the standard procedures for optical, chemical, biological, electrochemiluminescent and fluorescent detection. Additionally, applications for the use of non-isotopically labelled biomolecules are described. Specific protocols are given for hybridization analysis such as blot, colony/plaque and in-situ hybridization formats, and also non-radioactive techniques for nucleic acid sequencing and amplification. Each chapter contains a short introduction, a detailed description of the method with lab protocols, trouble-shooting tips and references.

CENP-B binds a novel centromeric sequence in the Asian mouse Mus caroli.

Abstract: Minor satellite DNA, found atMus musculuscentromeres, is not present in the genome of the Asian mouse Mus caroli. This repetitive sequence family is speculated to have a role in centromere function by providing an array of binding sites for the centromere-associated protein CENP-B. The apparent absence of CENP-B bindingsitesintheM.caroligenomeposesamajorchallengetothishypothesis.Herewedescribetwoabundant satellite DNA sequences present at M. caroli centromeres. These satellites are organized as tandem repeat arrays, over 1 Mb in size, of either 60- or 79-bp monomers. All autosomes carry both satellites and small amounts of a sequence related to theM. musculusmajor satellite. The Y chromosome contains small amounts of both major satellite and the 60-bp satellite, whereas the X chromosome carries only major satellite sequences. M. caroli chromosomes segregate in M. caroli 3 M. musculus interspecific hybrid cell lines, indicatingthatthetwosetsofchromosomescaninteractwiththesamemitoticspindle.UsingapolyclonalCENP-B antiserum, we demonstrate thatM. carolicentromeres can bind murine CENP-B in such an interspecific cell line, despite the absence of canonical 17-bp CENP-B binding sites in theM. caroligenome. Sequence analysis of the 79-bp M. caroli satellite reveals a 17-bp motif that contains all nine bases previously shown to be necessary for in vitro binding of CENP-B. ThisM. carolimotif binds CENP-B from HeLa cell nuclear extract in vitro, as indicated by gel mobility shift analysis. We therefore suggest that this motif also causes CENP-B to associate with M. caroli centromeres in vivo. Despite the sequence differences, M. caroli presents a third, novel mammalian centromeric sequence producing an array of binding sites for CENP-B.

Distinctive patterns of histone H4 acetylation are associated with defined sequence elements within both heterochromatic and euchromatic regions of the human genome

Abstract: The pattern of histone H4 acetylation in different genomic regions has been investigated by immunoprecipitating oligonucleosomes from a human lymphoblastoid cell line with antibodies to H4 acetylated at lysines 5, 8, 12 or 16. DNA from antibody-bound or unbound chromatin was assayed by slot blotting. Pol I and pol II transcribed genes located in euchromatin were shown to have levels of H4 acetylation at lysines 5, 8 and 12 equivalent to those in input chromatin, but to be slightly enriched in H4 acetylated at lysine 16. In no case did the acetylation level correlate with actual or potential transcriptional activity. All acetylated histone H4 isoforms were depleted in non-coding, simple repeat DNA in heterochromatin, though the extent of depletion varied with the type of heterochromatin and with the isoform. Two single copy genes that map within or adjacent to blocks of paracentric heterochromatin are depleted in H4 acetylated at lysines 5, 8 and 12, but not 16. Consensus sequences of repetitive elements of the Alu family (SINES, enriched in R bands) were associated with H4 that was more highly acetylated at all four lysines than input chromatin, while H4 associated with Kpn I elements (LINES, enriched in G bands) was significantly underacetylated.

A review of fluorescence in situ hybridization (FISH): current status and future prospects.

Abstract: Fluorescence in situ hybridization (FISH) is a powerful technique for detecting DNA or RNA sequences in cells, tissues and tumors. This molecular cytogenetic technique enables the localization of specific DNA sequences within interphase chromatin and metaphase chromosomes and the identification of both structural and numerical chromosome changes. FISH is quickly becoming one of the most extensively used cytochemical staining techniques owing to its sensitivity and versatility, and with the improvement of current technology and cost effectiveness, its use will surely continue to expand. Here we review the wide variety of current applications and future prospects of FISH technology.