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Comparative EST analyses provide insights into gene expression in two asexual developmental stages of Eimeria tenella

Ng ST, Sanusi Jangi M, Shirley MW, Tomley FM, Wan KL

Exp Parasitol, 2002 11 13;101(2-3):168-73.
PMID: 12427472

The protozoan parasite Eimeria tenella has a complex life cycle that includes two major asexual developmental stages, the merozoite and the sporozoite. The expressed sequence tag (EST) approach has been previously used to study gene expression of merozoites. We report here the generation and analysis of 556 ESTs from sporozoites. Comparative analyses of the two datasets reveal a number of transcripts that are preferentially expressed in a specific stage, including previously uncharacterised sequences. The data presented indicate the invaluable potential of the comparative EST analysis for providing information on gene expression patterns in the different developmental stages of E. tenella.

Matched MeSH terms: Gene Expression Regulation, Developmental/genetics*
De novo hotspot variants in CYFIP2 cause early-onset epileptic encephalopathy

Nakashima M, Kato M, Aoto K, Shiina M, Belal H, Mukaida S, et al.

Ann Neurol, 2018 04;83(4):794-806.
PMID: 29534297 DOI: 10.1002/ana.25208

OBJECTIVE: The cytoplasmic fragile X mental retardation 1 interacting proteins 2 (CYFIP2) is a component of the WASP-family verprolin-homologous protein (WAVE) regulatory complex, which is involved in actin dynamics. An obvious association of CYFIP2 variants with human neurological disorders has never been reported. Here, we identified de novo hotspot CYFIP2 variants in neurodevelopmental disorders and explore the possible involvement of the CYFIP2 mutants in the WAVE signaling pathway.
METHODS: We performed trio-based whole-exome sequencing (WES) in 210 families and case-only WES in 489 individuals with epileptic encephalopathies. The functional effect of CYFIP2 variants on WAVE signaling was evaluated by computational structural analysis and in vitro transfection experiments.
RESULTS: We identified three de novo CYFIP2 variants at the Arg87 residue in 4 unrelated individuals with early-onset epileptic encephalopathy. Structural analysis indicated that the Arg87 residue is buried at an interface between CYFIP2 and WAVE1, and the Arg87 variant may disrupt hydrogen bonding, leading to structural instability and aberrant activation of the WAVE regulatory complex. All mutant CYFIP2 showed comparatively weaker interactions to the VCA domain than wild-type CYFIP2. Immunofluorescence revealed that ectopic speckled accumulation of actin and CYFIP2 was significantly increased in cells transfected with mutant CYFIP2.
INTERPRETATION: Our findings suggest that de novo Arg87 variants in CYFIP2 have gain-of-function effects on the WAVE signaling pathway and are associated with severe neurological disorders. Ann Neurol 2018;83:794-806.

Matched MeSH terms: Gene Expression Regulation, Developmental/genetics
Regulation of gene expression mediating indeterminate muscle growth in teleosts

Ahammad AK, Asaduzzaman M, Asakawa S, Watabe S, Kinoshita S

Mech. Dev., 2015 Aug;137:53-65.
PMID: 25842264 DOI: 10.1016/j.mod.2015.02.006

Teleosts are unique among vertebrates due to their indeterminate muscle growth, i.e., continued production of neonatal muscle fibers until death. However, the molecular mechanism(s) underlying this property is unknown. Here, we focused on the torafugu (Takifugu rubripes) myosin heavy chain gene, MYHM2528-1, which is specifically expressed in neonatal muscle fibers produced by indeterminate muscle growth. We examined the flanking region of MYHM2528-1 through an in vivo reporter assay using zebrafish (Danio rerio) and identified a 2100 bp 5'-flanking sequence that contained sufficient promoter activity to allow specific gene expression. The effects of enhanced promoter activity were observed at the outer region of the fast muscle and the dorsal edge of slow muscle in zebrafish larvae. At the juvenile stage, the promoter was specifically activated in small diameter muscle fibers scattered throughout fast muscle and in slow muscle near the septum separating slow and fast muscles. This spatio-temporal promoter activity overlapped with known myogenic zones involved in teleost indeterminate muscle growth. A deletion mutant analysis revealed that the -2100 to -600 bp 5'flanking sequence of MYHM2528-1 is essential for promoter activity. This region contains putative binding sites for several representative myogenesis-related transcription factors and nuclear factor of activated T-cell (NFAT), a transcription activator involved in regeneration of mammalian adult skeletal muscle. A significant reduction in the promoter activity of the MYHM2528-1 deletion constructs was observed in accordance with a reduction in the number of these binding sites, suggesting the involvement of specific transcription factors in indeterminate muscle growth.

Matched MeSH terms: Gene Expression Regulation, Developmental/genetics*
Expression of proteins related to thyroid hormone function in the uterus is down-regulated at the day of implantation in hypothyroid pregnant rats

Salleh N, Sayem ASM, Giribabu N, Khaing SL

Cell Biol Int, 2019 May;43(5):486-494.
PMID: 30761678 DOI: 10.1002/cbin.11114

Hypothyroidism has been linked to infertility, but the mechanisms underlying infertility-related hypothyroidism have yet to be fully elucidated. Therefore, in this study, effects of hypothyroidism on expression of the proteins related to thyroid hormone function in the uterus, which were thought to play a role implantation, including thyroid hormone receptor (TR), thyroid stimulating hormone receptor (TSHR), retinoic acid receptor (RAR) and extracellular kinase (ERK) were identified. Pregnant female rats were rendered hypothyroid by giving methimazole (MMI), orally. Following hypothyroid induction, rats were grouped into control (non-treated) and received subcutaneous thyroxine at 20, 40, and 80 μg/kg/day for five consecutive days. At Day 6, which is the day of implantation (GD 6), rats were sacrificed and the number of embryo implantation site in the uterus was calculated. Then, uterine horns were harvested and expression of the above proteins and their mRNAs were identified by Western blotting and real-time PCR, respectively. In non-treated hypothyroid pregnant rats, the number of embryo implantation sites decreased as compared to euthyroid and hypothyroid rats receiving thyroxine treatment. Similarly, expression of TRα-1, TRβ-1, TSHR, ERK1/2 and RAR proteins and mRNA in the uterus of non-treated hypothyroid rats also decreased (P

Matched MeSH terms: Gene Expression Regulation, Developmental/genetics