Project description:Beef marbling is caused by intramuscular deposition, and it is an economically important trait in the beef industry. Vitamin A (VA) is an important feed supplement for cattle, but it can hinder marbling if provided in excess. In cattle, VA forms various derivatives such as all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9cRA). Therefore, we investigated the genes involved in bovine intramuscular adipogenesis after VA treatment with ATRA and 9cRA. Differential gene expression levels were validated by microarray analysis in a clonal bovine intramuscular preadipocyte (BIP) cell line derived from the intramuscular adipose tissue of Japanese Black cattle. BIP cells were harvested six days after adipogenic stimulation with either 1 μM ATRA, 1 μM 9cRA, or nonretinoic acids control. The ATRA- and 9cRA-treated cells exhibited reduced transcription of genes involved in the circulatory system and muscle development compared with the no retinoic acid (RA) treatment. In addition, the ATRA- and 9cRA-treated cells exhibited increased transcription of genes involved in the immune system, protein kinase B signaling, and responses to various stimuli. These results demonstrate the lower expression of muscle development in ATRA- and 9cRA-treated BIP cells during adipogenesis.
Project description:The black nectar of Melianthus flowers is thought to serve as a visual attractant to pollinators, but the chemical identity and synthesis of the black pigment are unknown. Here we report that the black nectar contains a natural analog of iron-gall ink, which humans have used since medieval times. Specifically, dark black nectar at anthesis contains high levels of ellagic acid and iron; synthetic solutions of ellagic acid and iron(III) recapitulate the black color of the nectar. Conversely, lightly colored nectars before and after anthesis contain significantly lower levels of ellagic acid and iron, but higher levels of gallic acid. We then explored the possibility of post-secretory synthesis of ellagic acid from gallic acid. Indeed, Melianthus nectar contains a peroxidase that oxidizes gallic acid to form ellagic acid. Reactions containing the nectar peroxidase, gallic acid, hydrogen peroxide, and iron can fully recreate the black color of the nectar. Visual modeling indicates that the black color is both visible and conspicuous to birds within the context of the flower. In summary, the black nectar of Melianthus is derived from an ellagic acid-Fe complex analogous to iron-gall ink and is likely involved in the attraction of passerine bird pollinators.
Project description:Beef marbling is caused by intramuscular deposition, and it is an economically important trait in the beef industry. Vitamin A (VA) is an important feed supplement for cattle, but it can hinder marbling if provided in excess. In cattle, VA forms various derivatives such as all-trans retinoic acid (ATRA) and 9-cis retinoic acid (9cRA). Therefore, we investigated the genes involved in bovine intramuscular adipogenesis after VA treatment with ATRA and 9cRA. Differential gene expression levels were validated by microarray analysis in a clonal bovine intramuscular preadipocyte (BIP) cell line derived from the intramuscular adipose tissue of Japanese Black cattle. BIP cells were harvested six days after adipogenic stimulation with either 1 ?M ATRA, 1 ?M 9cRA, or nonretinoic acids control. The ATRA- and 9cRA-treated cells exhibited reduced transcription of genes involved in the circulatory system and muscle development compared with the no retinoic acid (RA) treatment. In addition, the ATRA- and 9cRA-treated cells exhibited increased transcription of genes involved in the immune system, protein kinase B signaling, and responses to various stimuli. These results demonstrate the lower expression of muscle development in ATRA- and 9cRA-treated BIP cells during adipogenesis. BIP cells were cultured according to previously reported methods (Aso et al. 1995, Mizoguchi et al. 2014). Confluent cultures were transferred to fresh Dulbecco’s modified Eagle’s medium, which contained 50 ng/mL insulin, 0.25 ?M dexamethasone, 5 mM octanoate, 10 mM acetic acid, 10% fetal bovine serum, 100 U/mL penicillin, and 100 ?g/mL streptomycin. The cells were cultured for up to 6 days and the medium was changed every 2 days. BIP cells were treated with ATRA (1 ?M), 9cRA (1 ?M), or they received no treatment (control).
Project description:All-trans-retinoic acid (ATRA) has been successfully used in therapy of acute promyelocytic leukemia (APL), a cytogenetically distinct subtype of acute myeloid leukemia (AML) but the response of non-APL AML cases to ATRA-based treatment has been poor. Here we show that, via epigenetic reprogramming, inhibitors of LSD1/KDM1 demethylase including tranylcypromine (TCP) unlocked the ATRA-driven therapeutic response in non-APL AML. LSD1 inhibition did not lead to an increase in genome-wide H3 lysine4 dimethylation (H3K4me2) but did increase H3K4me2 and expression of myeloid differentiation-associated genes. Importantly, treatment with ATRA plus TCP dramatically diminished engraftment of primary human AML cells in vivo in NOD.SCID mice, suggesting that ATRA in combination with TCP may target leukemia-initiating cells. Furthermore, initiation of ATRA plus TCP co-treatment 15 days post-engraftment of human AML cells in NOD.SCID gamma mice also revealed the ATRA plus TCP drug combination to have a potent anti-leukemic effect, which was superior to treatment with either drug alone. These data identify LSD1 as a therapeutic target and strongly suggest that it may contribute to AML pathogenesis by inhibiting the normal pro-differentiative function of ATRA, paving the way for novel combinatorial therapies of AML. ChIP-seq was used to study the effects of ATRA, TCP and ATRA/TCP treatment on H3K4 dimethylation. In addition to the three treatment samples, two reference samples were processed: (i) An untreated sample using the same anti-H3K4me2 antibody and an untreated sample using IgG. These five sequencing experiments were conducted using HL-60 cells and TEX cells, leading to 10 ChIP-seq samples in total.
Project description:The pea aphid, Acyrthosiphon pisum, exhibits several environmentally cued polyphenisms, in which discrete, alternative phenotypes are produced. At low density parthenogenetic females produce unwinged female progeny, but at high density females produce progeny that develop with wings. These alternative phenotypes represent a solution to the competing demands of dispersal and reproduction. Males also develop as either winged or unwinged, but these alternatives are determined by a genetic polymorphism. Winged and unwinged males are morphologically less distinct from each other than winged and unwinged females, possibly because males experience fewer trade-offs between dispersal and reproduction. To assess whether shared physiological differences mirror the shared morphological differences that characterize the wing polyphenism and polymorphism, we used a cDNA microarray representing an estimated 10% of the coding genome (1734 genes) to examine differential transcript accumulation between winged and unwinged females and males. We identified several transcripts that differentially accumulate between winged and unwinged morphs in both sexes, the majority of which are involved in energy production. Unexpectedly, the extent of differential transcript accumulation between winged and unwinged morphs was greater for adult males than for adult females. Together, these results suggest not only that similar physiological differences underlie the polyphenism and polymorphism, but that male morphs, like females, are subject to trade-offs between reproduction and dispersal that are reflected in levels of transcript accumulation and possibly genome-wide patterns of gene regulation. These data also provide a baseline for future studies of the molecular and physiological basis of life history trade-offs. Keywords: Transcript levels were compared between winged and unwinged male and female pea aphids, for both nymphs and adults.
Project description:All-trans-retinoic acid (ATRA) has been successfully used in therapy of acute promyelocytic leukemia (APL), a cytogenetically distinct subtype of acute myeloid leukemia (AML) but the response of non-APL AML cases to ATRA-based treatment has been poor. Here we show that, via epigenetic reprogramming, inhibitors of LSD1/KDM1 demethylase including tranylcypromine (TCP) unlocked the ATRA-driven therapeutic response in non-APL AML. LSD1 inhibition did not lead to an increase in genome-wide H3 lysine4 dimethylation (H3K4me2) but did increase H3K4me2 and expression of myeloid differentiation-associated genes. Importantly, treatment with ATRA plus TCP dramatically diminished engraftment of primary human AML cells in vivo in NOD.SCID mice, suggesting that ATRA in combination with TCP may target leukemia-initiating cells. Furthermore, initiation of ATRA plus TCP co-treatment 15 days post-engraftment of human AML cells in NOD.SCID gamma mice also revealed the ATRA plus TCP drug combination to have a potent anti-leukemic effect, which was superior to treatment with either drug alone. These data identify LSD1 as a therapeutic target and strongly suggest that it may contribute to AML pathogenesis by inhibiting the normal pro-differentiative function of ATRA, paving the way for novel combinatorial therapies of AML.
Project description:All-trans retinoic acid (ATRA) exhibits significant therapeutic potential in various cancers, most notably for its success in treating acute promyelocytic leukemia (APL) by promoting differentiation. Beyond differentiation, ATRA can also induce cell cycle arrest, growth inhibition, and immune modulation in both hematopoietic and non-hematopoietic malignancies. Despite these multifaceted effects, the mechanisms driving ATRA efficacy remain incompletely understood, which has hindered its application to other cancers. To investigate the molecular basis of the anti-tumor actions of ATRA, we performed detailed time-series transcriptome analyses to identify key regulatory factors involved in ATRA's early transcriptional responses. Furthermore, chromatin immunoprecipitation sequencing (ChIP-seq) and functional assays evaluated the role of the key regulator, IRF1, to determine how it drives ATRA efficiency.
Project description:The genetic foundation of chicken tail feather color is not very well studied to date, though that of body feather color is extensively explored. In the present study, we used a synthetic chicken dwarf line (DW), which was originated from the hybrids between a black tail chicken breed, Rhode Island Red (RIR) and a white tail breed, Dwarf Layer (DL), to understand the genetic rules of the white/black tail color. The DW line still contain the individuals with black or white tails, even if the body feather are predominantly red, after more than ten generation of self-crossing and being selected for the body feather color. We firstly performed four crosses using the DW line chickens including black tail male to female, reciprocal crosses between the black and white, and white male to female to elucidate the inheritance pattern of the white/black tail. We found that (i) the white/black tail feather colors are independent of body feather color and (ii) the phenotype are autosomal simple trait and (iii) the white are dominant to the black in the DW lines. Furtherly, we performed a genome-wide association (GWA) analysis to determine the candidate genomic regions underlying the tail feather color by using black tail chickens from the RIR and DW chickens and white individuals from DW lines.
Project description:ATRA is an active metabolite of vitamin A that is frequently used for the treatment of acute promyelocytic leukemia (APL) patients. Despite the success of this treatment, some APL patients are refractory or relapse. This emphasis the need for new therapeutic strategies aiming to improve the anti-cancer effect of ATRA. We and other have previously shown that autophagy is activated during ATRA-induced granulocytic differentiation of acute promyelocytic leukemia cells. Although the transcription effect of ATRA on autophagy has been well-documented, little is known on the post-transcription/ post-translational regulation autophagy in response to ATRA. Given the importance of calcium ions in the control of autophagy, we hypothesized that calcium ions are involved in the initiation of autophagy by ATRA in APL cells. We thus examined how ATRA regulate intracellular calcium and sense perturbation of Ca2+ responses to autophagy, differentiation and cell death in APL cells.