An efficient method for constructing a random insertional mutant library for forward genetics in Nannochloropsis oceanica

Insertional mutation,phenotypic evaluation,and mutated gene cloning are widely used to clone genes from scratch.Exogenous genes can be integrated into the genome during non-homologous end joining(NHEJ)of the double-strand breaks of DNA,causing insertional mutation.The random insertional mutant library constructed using this method has become a method of forward genetics for gene cloning.However,the establishment of a random insertional mutant library requires a high transformation efficiency of exogenous genes.Many microalgal species show a low transformation efficiency,making constructing random insertional mutant libraries difficult.In this study,we established a highly efficient transformation method for constructing a random insertional mutant library of Nannochloropsis oceanica,and tentatively tried to isolate its genes to prove the feasibility of the method.A gene that may control the growth rate and cell size was identified.This method will facilitate the genetic studies of N.oceanica,which should also be a reference for other microalgal species.

Pigmentation Restored in Mutant Laboratory Strain of the Lady Beetle Coleomegilla maculata through Dietary Supplementation

A laboratory colony of Coleomegilla maculata (DeGeer), ye, selected for a pigmentation deficiency, was restored to near wild type cuticle coloration by adding crushed heads and wings of the red colored parental strain to the diet. While the wings and other colored portions of the cuticle re-gained the red color, the eyes of the pigmentation deficient insects were not changed from the pale mutant form. Plant derived carotenes lycopene and beta-carotene did not restore the mutant beetles to a visibly distinguishable red color. An additional pigmentation deficient mutant strain, gold, partially recovered red cuticle color when provided with diet containing pigmented insect particles. This work represents the first rescue of a color phenotype in a lady beetle.

Identification and Characterization of Reduced Epicuticular Wax Mutants in Rice

Epicuticular wax forms the outermost protective barrier of the aerial surfaces of land plants, working in concert with other components of the plant cuticle to prevent uncontrolled loss of water and to provide protection against an array of external environmental stress. In this study, chemically- mutagenized populations of rice （Oryza sativa L.） derived from approximately 4 750 M2 families were screened for adhesion of water droplets resulting in a wet leaf/glossy （wig） phenotype. Mutants were identified in 11 independently-derived M2 families. Scanning electron microscopy analysis confirmed the association of the wig phenotype with changes in the epicuticular wax crystals of these plants. The phenotypes of five mutants （7-17A, 26.1, 524.2, 680.2, and 843.1） were confirmed to be the result of single recessive gene mutation. Evaluation of mutants from 3 （6-1A, 7-17A, and 11-39A） of 11 M2 families revealed significant reductions （〉 50%） in surface wax content and increases in cuticle membrane permeability.

Pigmentation Restored in Mutant Laboratory Strain of the Lady Beetle <i>Coleomegilla maculata</i>through Dietary Supplementation

A laboratory colony of Coleomegilla maculata (DeGeer), ye, selected for a pigmentation deficiency, was restored to near wild type cuticle coloration by adding crushed heads and wings of the red colored parental strain to the diet. While the wings and other colored portions of the cuticle re-gained the red color, the eyes of the pigmentation deficient insects were not changed from the pale mutant form. Plant derived carotenes lycopene and beta-carotene did not restore the mutant beetles to a visibly distinguishable red color. An additional pigmentation deficient mutant strain, gold, partially recovered red cuticle color when provided with diet containing pigmented insect particles. This work represents the first rescue of a color phenotype in a lady beetle.

Benefiting others and self: Production of vitamins in plants

Vitamins maintain growth and development in humans, animals, and plants. Because plants serve as essential producers of vitamins, increasing the vitamin contents in plants has become a goal of crop breeding worldwide. Here, we begin with a summary of the functions of vitamins. We then review the achievements to date in elucidating the molecular mechanisms underlying how vitamins are synthesized, transported, and regulated in plants. We also stress the exploration of variation in vitamins by the use of forward genetic approaches, such as quantitative trait locus mapping and genome-wide association studies. Overall, we conclude that exploring the diversity of vitamins could provide new insights into plant metabolism and crop breeding.