Biology subjects

Stankovic, D.

Publications and source records attributed to Stankovic, D..

3 recordsLinked to original sources

bioRxiv2023

Electrochemical biosensor based on NAD(P)H-dependent Quinone Reductase for rapid and efficient detection of vitamin K3

Vitamin K refers to a group of vitamins that play an important role in blood coagulation and regulation of bone and vascular metabolism. However, vitamin K3 may give severe side effects in animal and humans when improperly added to food and feed due to its toxicity. Here, an electrochemical biosensor, based on the YaiB NADPH-dependent quinone reductase from Lactococcus lactis (YaiB), was developed to achieve rapid and redox probe-free detection of vitamin K3. First, we demonstrated the ability of the carbon electrode to distinguish between 1,4-benzoquinone and hydroquinone. Then, we engineered YaiB to work as a bioreceptor immobilized at the electrode and we demonstrated its sensitivity and specificity to reduce vitamin K3. Finally, to demonstrate the practical potential of the biosensor, we tested it directly in spiked milk samples, achieving 15-minute quantification of the vitamin K3. The limit of detection was 0.18M and 0.86 M in buffer and milk, respectively.

biophysics↗

bioRxiv2023

Xrp1 governs the stress response program to spliceosome dysfunction

Co-transcriptional processing of nascent pre-mRNAs by the spliceosome is vital to regulating gene expression and maintaining genome integrity. Here, we show that the deficiency of functional U5 snRNPs in Drosophila imaginal cells causes extensive transcriptome remodeling and accumulation of highly mutagenic R-loops, triggering a robust stress response and cell cycle arrest. Despite compromised proliferative capacity, the U5 snRNP deficient cells increased protein translation and cell size, causing intra-organ growth disbalance before being gradually eliminated via apoptosis. We identify the Xrp1-Irbp18 heterodimer as the primary driver of transcriptional and cellular stress program downstream of U5 snRNP malfunction. Knockdown of Xrp1 or Irbp18 in U5 snRNP deficient cells attenuated JNK and p53 activity, restored normal cell cycle progression and growth, and inhibited cell death. Reducing Xrp1-Irbp18, however, did not rescue the splicing defects and the organismal lethality, highlighting the requirement of accurate splicing for cellular and tissue homeostasis. Our work provides novel insights into the crosstalk between splicing and the DNA damage response and defines the Xrp1-Irbp18 heterodimer as a critical sensor of spliceosome malfunction.

cell biology↗

bioRxiv2022

Drosophila pVALIUM10 TRiP RNAi lines cause undesired silencing of Gateway-based transgenes

Post-transcriptional gene silencing using double-stranded RNA has revolutionized the field of functional genetics, allowing fast and easy disruption of gene function in various organisms. In Drosophila, many transgenic RNAi lines have been generated in large-scale efforts, including the Drosophila Transgenic RNAi Project (TRiP), to facilitate in vivo knockdown of virtually any Drosophila gene with spatial and temporal resolution. The available transgenic RNAi lines represent a fundamental resource for the fly community, providing an unprecedented opportunity to address a vast range of biological questions relevant to basic and biomedical research fields. However, caution should be applied regarding the efficiency and specificity of the RNAi approach. Here, we demonstrate that pVALIUM10-based RNAi lines, representing ~13% of the total TRiP collection (1,808 out of 13,410 TRiP pVALIUM-based RNAi lines), cause unintended off-target silencing of transgenes expressed from Gateway destination vectors generated via site-specific recombination. The silencing is mediated by targeting attB1 and attB2 sequences generated in the recombination reaction and included in the transcribed mRNA. Deleting these attB sites from the Gateway expression vector prevents silencing and restores expected transgene expression.

genetics↗