Microhair on the adaxial leaf surface of salt secreting halophytic Oryza coarctata Roxb. show distinct morphotypes: Isolation for molecular and functional analysis. (August 2019)

• Record Type: Journal Article
• Authors: Rajakani, Raja; Sellamuthu, Gothandapani; V, Saravanakumar; S, Kannappan; Shabala, Lana; Meinke, Holger; Chen, Zhonghua; Zhou, Meixue; Parida, Ajay; Shabala, Sergey; Venkataraman, Gayatri
• Is Part Of: Plant science. Volume 285(2019)
• Page Start: 248
• Page End: 257
• Publication Date: 2019-08
• Subjects: Salinity -- Microhair -- Bulliform cells -- Propidium iodide -- Percoll gradient -- RT-PCR; Botany -- Periodicals; Botanique -- Périodiques; 580
• DOI: 10.1016/j.plantsci.2019.05.004
• Languages: English
• ISSNs: 0168-9452

Abstract

Highlights: Microhairs on adaxial O. coarctata leaf surface have distinct morphotypes. Distal bulliform cells in O. coarctata leaves have microhairs (first report). A robust method developed to isolate viable microhairs from O. coarctata leaf. Microhair viability confirmed by PI staining, RT-PCR (trichome-specific OcWox3B ). Isolation protocol established can be used to elucidate salt secretory mechanisms. Abstract: Halophytic Oryza coarctata is a good model system to examine mechanisms of salinity tolerance in rice. O. coarctata leaves show the presence of microhairs in adaxial leaf surface furrows that secrete salt under salinity. However, detailed molecular and physiological studies of O. coarctata microhairs are limited due to their relative inaccessibility. This work presents a detailed characterization of O. coarctata leaf features. O. coarctata has two types of microhairs on the adaxial leaf surface: longer microhairs (three morphotypes) lining epidermal furrow walls and shorter microhairs (reported first time) arising from bulliform cells. Microhair morphotypes include (i) finger-like, tubular structures, (ii) tubular hairs with bilobed and flattened heads and (iii) bi-or trifurcated hairs. The unicellular nature of microhairs was confirmed by propidium iodide (PI) staining. An efficient method for the isolation and enrichment of O. coarctata microhairs is presented (yield averaging ˜2 × 10 5 /g leaf tissue). The robustness of the microhair isolation procedure was confirmed by subsequent viability staining (PI), total RNA isolation and RT-PCR amplification of O. coarctata trichome-specific WUSCHEL- related homeobox 3B ( OcWox3B ) and transporter gene-specific cDNA sequences. The present microhair isolation work from O. coarctata paves the way for examining genes involved in ion secretion in this halophytic wild rice model.