Abstract Detail

Evolutionary Developmental Biology (Evo-Devo)

Kostyun, Jamie [1], Zhang, Thompson [1], Patterson, Erin [1], Whipple, Clinton [2], Bartlett, Madelaine [3].

The pleiotropic developmental mutant tasselshealth3 encodes an essential mRNA processing factor.

Understanding phenotypic novelty and diversity requires examining the mechanisms and processes that control development. This is especially relevant in organisms that are genetic, evolutionary, or agricultural models – such as Zea mays (maize). We identified several maize mutants, called tasselshealth, that have extra leaves and reduced branching in tassels (male inflorescences). Using BSA-seq and fine mapping, we identified the gene disrupted in one of these mutants, tsh3, as the maize ortholog of Cleavage Stimulation Factor Subunit 77 (CstF77). CstF77 encodes a protein involved in 3’ processing of mRNA where it forms a complex with several other factors to identify polyadenylation sites, and is likely single copy across eukaryotes. Although initially identified as altering tassel architecture, the tsh3/cstF77 maize mutant phenotype is pleiotropic: total height, leaf attachment angle, transition to flowering, floral organ identity, ear phyllotaxy, seedling emergence and root growth are all affected. This pleiotropy may be at least partly due to mis-identification of polyadenylation (PA) sites across numerous mRNA targets, similar to systematic shifts in PA site usage identified in Arabidopsis thaliana cstf77 mutants. The severity of tsh3/cstf77 mutant phenotypes also varies between maize inbred lines, suggesting subtle variation in underlying developmental networks. Examining this mutant reveals how seemingly essential molecular processes (i.e. mRNA processing) can be modified to produce phenotypic variation.

1 - University Of Massachusetts, Biology, 611 North Pleasant St, Morrill III Rm 221, Amherst, MA, 01003, United States
2 - BYU Department Of Biology, 4102 Lsb, Provo, UT, 84602, United States
3 - University Of Massachusetts Amherst, Biology Department, 611 North Pleasant St., 221 Morrill 3, Amherst, MA, 01003, United States

Keywords:
development
pleiotropy
maize
genetic variation.

Presentation Type: Oral Paper
Session: EVDV1, Evolutionary Developmental Biology (Evo-Devo)
Location: Virtual/Virtual
Date: Thursday, July 30th, 2020
Time: 2:00 PM
Number: EVDV1016
Abstract ID:235
Candidate for Awards:None