Noncoding and coding transcriptome responses of a marine diatom to phosphate fluctuations

Area of Science:

• Marine biology
• Molecular biology
• Genomics

Background:

• Phosphorus is vital for marine life, but its concentration fluctuates, impacting phytoplankton.
• Diatoms are successful phytoplankton known for adapting to nutrient-poor conditions.
• The molecular basis of diatom adaptation to nutrient stress is not fully understood.

Purpose of the Study:

• To investigate global transcriptome changes in Phaeodactylum tricornutum under phosphorus fluctuations.
• To identify novel genes and regulatory mechanisms involved in phosphorus stress response.
• To explore the role of long intergenic nonprotein coding RNAs (lincRNAs) in phosphorus homeostasis.

Main Methods:

• Strand-specific RNA sequencing was used to analyze gene expression over 8 days.
• Global transcriptome changes in response to phosphorus fluctuations were monitored.
• Physiological states of the diatom were defined based on gene expression patterns.

Main Results:

• Five distinct physiological states were identified in Phaeodactylum tricornutum during phosphorus fluctuations.
• Previously unknown genes responsive to phosphorus stress were discovered.
• A complex sensory and signaling system involving bacterial and metazoan-like pathways was uncovered.
• Numerous novel lincRNAs specifically responsive to phosphorus depletion were identified.

Conclusions:

• The study provides molecular insights into the resilience and ecological success of diatoms.
• Identified lincRNAs suggest potential regulatory roles in phosphorus homeostasis.
• The findings open new avenues for exploring lincRNA function in diatoms under nutrient stress.