Related Experiment Video

Updated: Apr 27, 2026

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells
06:09

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells

Published on: June 7, 2019

8.6K

MicroRNA 340 is involved in UVB-induced dendrite formation through the regulation of RhoA expression in melanocytes

Qiang Jian1, Qing An1, Dongning Zhu1

  • 1Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.

Molecular and Cellular Biology
|July 2, 2014
PubMed

Insights

MicroRNAs (miRNAs) regulate skin cell dendrite formation after UV exposure. This study identifies microRNA 340 (miR-340) as a key regulator of UVB-induced dendrite development and melanosome transport.

Area of Science:

  • Molecular Biology
  • Cell Biology
  • Dermatology

Background:

  • UV irradiation influences skin pigmentation through complex mechanisms.
  • MicroRNAs (miRNAs) are crucial regulators of gene expression, impacting cellular processes.
  • The specific role of miRNAs in UV-induced melanocyte dendrite formation is not fully understood.

Purpose of the Study:

  • To investigate miRNA expression changes in response to UVB irradiation.
  • To identify mRNA targets of differentially expressed miRNAs involved in dendrite formation.
  • To elucidate the function of microRNA 340 (miR-340) in UVB-induced dendrite development and melanosome transport.

Main Methods:

  • Microarray screening to identify differentially expressed miRNAs after UVB exposure.
  • Bioinformatic analysis to predict mRNA targets of identified miRNAs.
  • Luciferase reporter assays to validate direct miRNA-mRNA interactions.
  • Overexpression and downregulation studies of miR-340 in human melanocytes (Pig1 cell line).

Main Results:

  • UVB irradiation altered miRNA expression profiles in melanocytes.
  • miR-340 was identified as a key miRNA regulating dendrite formation.
  • Overexpression of miR-340 enhanced dendrite formation and melanosome transport.
  • Downregulation of miR-340 inhibited UVB-induced dendrite formation and melanosome transport.
  • Direct targeting of RhoA by miR-340 was confirmed, with RhoA expression decreasing post-UVB.

Conclusions:

  • This study establishes a novel association between miR-340 and UVB irradiation response.
  • miR-340 plays a critical role in regulating UVB-induced melanocyte dendrite formation and melanosome transport.
  • The findings highlight miR-340 as a potential therapeutic target for managing UV-induced skin changes.

More Related Videos

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model12:37

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model

Published on: September 7, 2013

17.8K
Y-27632 Enriches the Yield of Human Melanocytes from Adult Skin Tissues08:06

Y-27632 Enriches the Yield of Human Melanocytes from Adult Skin Tissues

Published on: July 8, 2020

5.1K

Related Concept Videos

Small GTPases - Ras and Rho01:24

Small GTPases - Ras and Rho

Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
4.4K
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...
3.0K
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns—non-coding regions of a gene—or intergenic regions—stretches of DNA present between genes. Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After...
20.9K
MAPK Signaling Cascades01:07

MAPK Signaling Cascades

Mitogen-activated protein kinase, or MAPK pathway, activates three sequential kinases to regulate cellular responses such as proliferation, differentiation, survival, and apoptosis. The canonical MAPK pathway starts with a mitogen or growth factor binding to an RTK. The activated RTKs stimulate Ras, which recruits Raf or MAP3 Kinase (MAPKKK), the first kinase of the MAPK signaling cascade. Raf further phosphorylates and activates MEK or MAP2 Kinases (MAPKK), which in turn phosphorylates MAP...
7.3K
The Ras Gene02:38

The Ras Gene

The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a...
5.7K
Receptor Downregulation in MVBs01:15

Receptor Downregulation in MVBs

Multivesicular bodies (MVBs) are mature endosomes that sort ubiquitinated proteins and then fuse with lysosomes to degrade the sorted proteins. Epidermal growth factor (EGF) and its receptor (EGFR) form a complex that can be internalized through endocytosis, sorted into an MVB, and later degraded.
The EGFR can initiate signaling pathways that  lead to cell proliferation, migration, and differentiation. Overexpression of EGFR  stimulates cells to proliferate. Excessive  EGFR...
2.0K