Insertional Mutagenesis as a Strategy to Open New Paths in Microalgal Molybdenum and Nitrate Homeostasis

• DOI: 10.20944/preprints202504.2140.v1
• Publication Date: 2025-04-28T01:23:40Z
• Authors: Esperanza Leon-Mi...; Manuel Tejada-Jim...; Angel Llamas
• Keywords: Insertional mutagenesis; Homeostasis

Molybdenum (Mo) is a vital micronutrient for nearly all living organisms, serving as cofactor molybdoenzymes that catalyze essential redox reactions in nitrogen metabolism. Among these enzymes nitrate reductase plays crucial role assimilation. Maintaining Mo homeostasis—including uptake, storage, and utilization—is critical to avoid both deficiency toxicity. Our research focuses on uncovering novel molecular components involved homeostasis, particularly connection with assimilation, using Chlamydomonas reinhardtii, model green microalga. To achieve this, we generated over 5,000 transformants through insertional mutagenesis paromomycin resistance cassette (AphVIII) screened them altered growth under different concentrations. We identified four strains showing pattern when source or exhibiting increased sensitivity Mo. The genomic alterations were identified. Notably, Mo-resistant Mo-sensitive transformant had disruptions genes encoding ABC-type transport proteins, indicating potential proteins transport. Additionally, two unable grow nitrate. One of mutation the CNX7, gene biosynthesis, while other BAT1, an amino acid transporter. BAT1 mutant represents interesting case study, this has not previously been associated These findings enhance our understanding homeostasis mechanisms open new paths engineering microalgae improved