Project description:We performed microRNA microarray analysis to determine microRNAs that are differentially expressed between the differentiated hfRPE monolayer (pigmented, hexagonally packed) and dedifferentiated hfRPE cells (non-pigmented, fibroblast-like). Experiment was performed using the Agilent-019118 Human miRNA Microarray 2.0 G4470B.
Project description:Information about protein expression in rice grain across both pigmented and non-pigmented rice varieties is still relatively scarce. The data provided here represent proteomic data obtained from selected 6 Malaysian local rice varieties with varying pigmentations (black, red and white). The selected pigmented rice varieties such as black (BALI and Pulut hitam 9) and red rice (MRQ100 and MRM16) have shown high antioxidant activities and non-pigmented rice (MRQ76 and MR297) contain amino acid and micronutrient contents. This project aimed to obtain global protein expression profile as well as differential protein expression between the selected pigmented and non-pigmented rice varieties particularly proteins with their functions responsible for nutritional (i.e. antioxidant, folate and low glycaemic index) and quality (i.e. aromatic) traits. Integration of this proteomics dataset with other available in-house omics data could facilitate the identification of significant functional markers related to nutritional and quality traits. Total proteins were prepared from dehusked matured seeds harvested from three different rice plants of each variety (3 protein samples per variety). The proteins were trypsin digested before subjected to SWATH-MS proteomics analysis. Proteins were identified by matching tandem mass (MS/MS) spectra from both 1D and 2D IDA to Oryza sativa japonica and indica rice databases available at UniProt by using ProteinPilot software (v4.2) (AB Sciex). Quantification of proteins was carried out by determining protein peak areas extracted from SWATH analysis data sets using PeakView (v2.1) (AB Sciex) software. Differentially expressed protein between varieties were identified using T-test analysis with a set threshold for fold change ± 1.5 and p‐value < 0.05.
Project description:The hair follicle bulb is the only site of pigment production for the hair shaft and melanogenically active melanocytes are located in the upper hair matrix. We conducted a microarray study to discover gene expression patterns that may be implicated in the lack of melanogenesis in gray hair follicles (HF). Pigmented and non-pigmented HFs collected from the same individuals were micro-dissected into the lower one third including the hair bulb (HB) and the upper hair shaft and sheaths (HS) including the bulge region. Microarray data was verified with qPCR and immunohistochemistry. Target effects were evaluated in vitro on human epidermal melanocytes (HEMs). In comparison to pigmented HS and HBs, several nucleotide excision repair (NER) family genes exhibited statistically significant lower expression both in non-pigmented HS and non-pigmented HB. These genes were identified as ERCC1, ERCC2, ERCC3, ERCC4, ERCC5, ERCC6, XPA, NTPBP, HCNP, DDB2 and POLH. Immunohistochemistry showed consistent results. By siRNA interference we also detected that a deficiency in ERCC3 in melanocytes reduced the ability to produce melanin in vitro. Our results suggest that loss of NER gene function may lead to DNA damage and mutation accumulation in melanocytes, which may possibly lead to cell death. Further, a loss of ERCC3 function may lead to reduced gene transcription and this in turn may lead to reduced melanin production ability. These results offer a new insight into the molecular changes that occur in non-pigmented HF and may also provide novel information with regard to melanogenesis and its regulation.
