Abstract
Cotton (Gossypium spp.) is the world’s third most important oilseed crop as well as an economic source of protein. However, the presence of (-)- gossypol limits the nutritional value of cottonseeds. To genetically profile relevant traits, seeds of the two cotton parental lines TM-1 (G. hirstum) and 3-79 (G. barbadense) along with their 17 chromosomal substitution (CS) progenies were quantified for (-)- and (+)- enantiomer levels. The TM-1 parent was found to contain a higher ratio of (+)-:(-)- gossypol enantiomers (13.34:8.52 µg/mg) compared to that of 3-79 levels (6.69:7.41 µg/mg) in the seeds. Among progeny CS-B (containing substituted chromosomes from G. barbadense in G. hirsutum background) lines, only CS-B17 was found to contain significantly lower (7.65 µg/mg) level of (+)-enantiomer in its seeds, and also had the lowest (5.09 µg/mg) amount of (-)- gossypol among all lines. A singular protocol was then devised for RNA yields from polysaccharide-rich cottonseeds of CS-B17 and its parents. Transcription derived fragments (TDFs) analyses of these three lines were conducted on seeds harvested at 28, 35 and 42 days post anthesis (DPA). 64 TDFs profiles were analyzed using differential expression analyses, and similarities were revealed between 3-79 and CS-B17 along with unique expression trends for CS-B17. Such expression analyses, which are based on single chromosome differences with TM-1 parent while reflecting seed nutritional merit of 3-79 parent, may facilitate cotton breeding endeavors. Keywords: Chromosome substituted lines; Cotton; High performance liquid chromatography; Nutrition traits; RNA extraction; Transcription derived fragments http://dx.doi.org/10.19045/bspab.2019.80129
Highlights
G. barbadense in G. hirsutum background) lines, only chromosomal substitution (CS)-B17 was found to contain significantly lower (7.65 μg/mg) level of (+)-enantiomer in its seeds, and had the lowest (5.09 μg/mg) amount of (-)- gossypol among all lines
Though G. barbadense has higher O-methylated gossypol derivatives [16], it is reported with lower levels of (-)- gossypol compared to G. hirsutum [28] and may have desirable seed usage traits
CS-B17 seeds have been found to contain high levels of protein and oil compared to both parents [31]
Summary
Cottonseeds are very high in polysaccharides, a modified CTAB based protocol [22, 23] combined with. Technologies) was required for extracting high quality RNA for expression profiling. Polyvinylpyrrolidone (PVP) for dissolving membranes, inactivating ribonucleases, disrupting protein-nucleic acid interactions while removing polysaccharides, polyphenols and other secondary metabolites [29]. At 65oC, CTAB reagent induced binding with polysaccharides (inhibits PCR amplifications), whereas phenolic compounds (powerful oxidizing agents covalently bonding with nucleic acids) were inactivated (forming hydrogen bonds) by PVP together with the extraction buffer. Addition of salt in the extraction buffer prevented bonding between polysaccharides and CTAB-RNA complexes and favored the removal of polysaccharides and CTAB during chloroform extraction [30]. Positive ions (Na+) in salt neutralized the negative charges of phosphates in the nucleic acids, allowing these to compact during extraction while beta-mercaptoethanol (added just before use), a strong reducing agent, helped to denature RNases and cleaned tannins and other polyphenols.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
