Differentially regulated gene expression in quiescence versus senescence and identification of ARID5A as a quiescence associated marker.

In multicellular organisms majority of the cells remain in a non-dividing states of either quiescence (reversible) or senescence (irreversible). In the present study, gene expression signatures unique to quiescence and senescence were identified using microarray in osteosarcoma cell line, U2OS. It was noted that certain genes and pathways like NOD pathway was shared by both the growth arrest conditions. A major highlight of the present study was increased expression of number of chemokines and cytokines in both quiescence and senescence. While senescence-associated secretory phenotype (SASP) is well known, the quiescence-associated secretory phenotype (QASP) is relatively unknown and appeared novel in this study. ARID5A, a subunit of SWI/SNF complex was identified as a quiescence associated gene. The endogenous expression of ARID5A increased during serum starved condition of quiescence. Overexpression of ARID5A resulted in more number of cells in G0/G1 phase of cell cycle. Further ARID5A overexpressing cells when subjected to serum starvation showed a pronounced secretory phenotype. Overall, the present work has identified gene expression signatures which can distinguish quiescence from senescence.

Evaluation of Apis mellifera syriaca Levant region honeybee conservation using comparative genome hybridization.

Apis mellifera syriaca is the native honeybee subspecies of Jordan and much of the Levant region. It expresses behavioral adaptations to a regional climate with very high temperatures, nectar dearth in summer, attacks of the Oriental wasp and is resistant to Varroa mites. The A. m. syriaca control reference sample (CRS) in this study was originally collected and stored since 2001 from "Wadi Ben Hammad", a remote valley in the southern region of Jordan. Morphometric and mitochondrial DNA markers of these honeybees had shown highest similarity to reference A. m. syriaca samples collected in 1952 by Brother Adam of samples collected from the Middle East. Samples 1-5 were collected from the National Center for Agricultural Research and Extension breeding apiary which was established for the conservation of A. m. syriaca. Our objective was to determine the success of an A. m. syriaca honey bee conservation program using genomic information from an array-based comparative genomic hybridization platform to evaluate genetic similarities to a historic reference collection (CRS). Our results had shown insignificant genomic differences between the current population in the conservation program and the CRS indicated that program is successfully conserving A. m. syriaca. Functional genomic variations were identified which are useful for conservation monitoring and may be useful for breeding programs designed to improve locally adapted strains of A. m. syriaca.

Molecular Delineation of Partial Trisomy 14q and Partial Trisomy 12p in a Patient with Dysmorphic Features, Heart Defect and Developmental Delay.

This study describes a molecular analysis of partial trisomy 14q and partial trisomy 12p in a 5-year-old male child presenting with dysmorphic features, congenital heart disease and global developmental delay. Chromosomal analysis of the patient with GTG bands revealed a 47,XY,+der(14)t(12;14)(p13;q22)mat karyotype; the mother's karyotype was 46,XX,t(12;14)(p13;q22). Further, oligonucleotide array- CGH studies revealed an amplification of 32.3 Mb in the 14q11.1q22.1 region, substantiating partial trisomy 14q and additionally displaying an amplification of ∼1 Mb in the 12p13.3pter region for partial trisomy 12p. This is the first study to demonstrate a novel association of partial trisomies of 14q and 12p due to a 3:1 segregation of a maternal balanced translocation involving chromosomes 12 and 14. Gene ontology studies indicated 5 potential candidate genes in the amplified regions for the observed congenital anomalies.

Whole genome response in guinea pigs infected with the high virulence strain Mycobacterium tuberculosis TT372.

In this study we conducted a microarray-based whole genomic analysis of gene expression in the lungs after exposure of guinea pigs to a low dose aerosol of the Atypical Beijing Western Cape TT372 strain of Mycobacterium tuberculosis, after harvesting lung tissues three weeks after infection at a time that effector immunity is starting to peak. The infection resulted in a very large up-regulation of multiple genes at this time, particularly in the context of a "chemokine storm" in the lungs. Overall gene expression was considerably reduced in animals that had been vaccinated with BCG two months earlier, but in both cases strong signatures featuring gamma interferon [IFNγ] and tumor necrosis factor [TNFα] were observed indicating the potent TH1 response in these animals. Even though their effects are not seen until later in the infection, even at this early time point gene expression patterns associated with the potential emergence of regulatory T cells were observed. Genes involving lung repair, response to oxidative stress, and cell trafficking were strongly expressed, but interesting these gene patterns differed substantially between the infected and vaccinated/infected groups of animals. Given the importance of this species as a relevant and cost-effective small animal model of tuberculosis, this approach has the potential to provide new information regarding the effects of vaccination on control of the disease process.