Northern Blot analysis of FaZnF and P5CS expression. (A) Northern Blot analysis of FaZnF and P5CS expression in response to salt stress for various time periods (0-24 hr). Total RNA was extracted from the aerial portions of plants that had been treated with 500 mM NaCl for the indicated number of hours. (B) Analysis of transcript levels of FaZnF and P5CS from plants treated with different levels of NaCl (0-500 mM) for 12 or 24 hr. Total RNA was extracted from the aerial portions of the plants that had been treated with different levels of NaCl (100-500 mM) for 12 or 24 hr, or with water (0 hr control). Ten μg of total RNA from each treatment was separated on a denaturing (formaldehyde) agarose gel. Equal loading was confirmed by visualization of the rRNA bands with ethidium bromide before (gel) and after transfer to the nylon membrane (blot). The RNA blots were hybridized with DIG-labeled DNA probes for ZNF1 and P5CS.