MiR-410 Acts as a Tumor Suppressor in Estrogen Receptor-Positive Breast Cancer Cells by Directly Targeting ERLIN2 via the ERS Pathway.

Background/aims: Endoplasmic reticulum lipid raft-associated 2 (ERLIN2) is reported to be overexpressed in human breast cancer cells and plays an important role in cell proliferation. MicroRNAs (miRNAs) act as post-transcriptional regulators of gene expression and are involved in the development of multiple malignancies, including breast cancer. However, the molecular mechanism of the aberrant ERLIN2 expression in human breast cancer remains poorly understood.

A Pacifastacus leniusculus serine protease interacts with WSSV.

Serine proteases are involved in many critical physiological processes including virus spread and replication. In the present study, we identified a new clip-domain serine protease (PlcSP) in the crayfish Pacifastacus leniusculus hemocytes, which can interact with the White Spot Syndrome Virus (WSSV) envelope protein VP28. It was characterized by a classic clip domain with six strictly conserved Cys residues, and contained the conserved His-Asp-Ser (H-D-S) motif in the catalytic domain.

20-Hydroxyecdysone (20E) Primary Response Gene E93 Modulates 20E Signaling to Promote Bombyx Larval-Pupal Metamorphosis.

As revealed in a previous microarray study to identify genes regulated by 20-hydroxyecdysone (20E) and juvenile hormone (JH) in the silkworm, Bombyx mori, E93 expression in the fat body was markedly low prior to the wandering stage but abundant during larval-pupal metamorphosis. Induced by 20E and suppressed by JH, E93 expression follows this developmental profile in multiple silkworm alleles. The reduction of E93 expression by RNAi disrupted 20E signaling and the 20E-induced autophagy, caspase activity, and cell dissociation in the fat body.

Bombyx E75 isoforms display stage- and tissue-specific responses to 20-hydroxyecdysone.

Resulted from alternative splicing of the 5' exons, the nuclear receptor gene E75 in the silkworm, Bombyx mori, processes three mRNA isoforms, BmE75A, BmE75B and BmE75C. From the early 5(th) larval instar to the prepupal stages, BmE75A mRNA and protein levels in the prothoracic glands display developmental profiles similar to ecdysteroid titer. In the fat body, mRNA levels but not protein levels of all three BmE75 isoforms correlate with ecdysteroid titer; moreover, proteins of all three BmE75 isoforms disappear at the prepupal stages, and a modified BmE75 protein with smaller molecular weight and cytoplasm localization occurs.

Hijacking of host calreticulin is required for the white spot syndrome virus replication cycle.

We have previously shown that multifunctional calreticulin (CRT), which resides in the endoplasmic reticulum (ER) and is involved in ER-associated protein processing, responds to infection with white spot syndrome virus (WSSV) by increasing mRNA and protein expression and by forming a complex with gC1qR and thereby delaying apoptosis. Here, we show that CRT can directly interact with WSSV structural proteins, including VP15 and VP28, during an early stage of virus infection. The binding of VP28 with CRT does not promote WSSV entry, and CRT-VP15 interaction was detected in the viral genome in virally infected host cells and thus may have an effect on WSSV replication.

20-Hydroxyecdysone upregulates Atg genes to induce autophagy in the Bombyx fat body.

Autophagy is finely regulated at multiple levels and plays crucial roles in development and disease. In the fat body of the silkworm, Bombyx mori, autophagy occurs and Atg gene expression peaks during the nonfeeding molting and pupation stages when the steroid hormone (20-hydroxyecdysone; 20E) is high. Injection of 20E into the feeding larvae upregulated Atg genes and reduced TORC1 activity resulting in autophagy induction in the fat body.

Genome-wide identification and characterization of ATP-binding cassette transporters in the silkworm, Bombyx mori.

Background: The ATP-binding cassette (ABC) transporter superfamily is the largest transporter gene family responsible for transporting specific molecules across lipid membranes in all living organisms. In insects, ABC transporters not only have important functions in molecule transport, but also play roles in insecticide resistance, metabolism and development.

Results: From the genome of the silkworm, Bombyx mori, we have identified 51 putative ABC genes which are classified into eight subfamilies (A-H) by phylogenetic analysis.

Genome-wide regulation of innate immunity by juvenile hormone and 20-hydroxyecdysone in the Bombyx fat body.

Background: Insect innate immunity can be affected by juvenile hormone (JH) and 20-hydroxyecdysone (20E), but how innate immunity is developmentally regulated by these two hormones in insects has not yet been elucidated. In the silkworm, Bombyx mori, JH and 20E levels are high during the final larval molt (4 M) but absent during the feeding stage of 5(th) instar (5 F), while JH level is low and 20E level is high during the prepupal stage (PP). Fat body produces humoral response molecules and hence is considered as the major organ involved in innate immunity.

Developmental regulation of glycolysis by 20-hydroxyecdysone and juvenile hormone in fat body tissues of the silkworm, Bombyx mori.

20-Hydroxyecdysone (20E) and juvenile hormone (JH) control a variety of physiological events during insect development and metamorphosis. To understand how 20E and JH developmentally regulate energy metabolism in insects, we performed a genome-wide microarray analysis of fat body tissues isolated from the silkworm, Bombyx mori. Many genes involved in energy metabolism, including genes in the glycolytic pathway, were down-regulated during molting and pupation, when 20E levels are high.