Table of Contents
What is barnase and barstar system?
The barnase-barstar transgene based hybrid seed production technology has been commercially deployed in crops like Brassica napus (Mariani et al. 1990; 1992). The system utilizes the expression of barnase gene, encoding cytotoxic RNase protein in the tapetum cells to make one of the combiner’s male sterile.
What is transgenic male sterility?
Transgenic male sterility is controlled by foreign nuclear genes. In this system two types of transgenes, viz., barnase and barstar are used. The gene barnase causes male sterility and the gene barstar restores the fertility. Both these genes have been utilized from the bacterium Bacillus amyloliquefaciens.
What is barnase gene?
Barnase (a portmanteau of “BActerial” “RiboNucleASE”) is a bacterial protein that consists of 110 amino acids and has ribonuclease activity. It is synthesized and secreted by the bacterium Bacillus amyloliquefaciens, but is lethal to the cell when expressed without its inhibitor barstar.
What is male sterility and its types?
Types of Male Sterility: The male sterility is of five types 1) Genetic male sterility, 2) Cytoplasmic male sterility, 3) Cytoplasmic genetic male sterility, 4) Chemical induced male sterility and 5) Transgenic male sterility.
What is the biological function of barnase?
Recoverable block of function Barnase encodes a potent ribonuclease, which when expressed, kills a cell because it chews up the whole protein manufacturing system.
Who discovered male sterility?
Joseph Gottlieb Kölreuter
Joseph Gottlieb Kölreuter was the first to document male sterility in plants. In the 18th century, he reported on anther abortion within species and specific hybrids. Cytoplasmic male sterility (CMS) has now been identified in over 150 plant species.
What are the mechanisms of male sterility?
Abstract. In plants, male sterility can be caused either by mitochondrial genes with coupled nuclear genes or by nuclear genes alone; the resulting conditions are known as cytoplasmic male sterility (CMS) and genic male sterility (GMS), respectively.
What are the three types of male sterility?
(3) Cytoplasmic genetic male sterility. There are two other types, viz., chemical induced male sterility, and transgenic male sterility. Almost all crop plants possess male sterility if investigated property.
What is male sterility PDF?
Male sterility is characterized by nonfunctional pollen grains, while female gametes function normally. Inability to produce or to release viable or functional pollen as. a result of failure of formation or development of functional. stamens, microspores or gametes.
What is CMS line?
Three-line system, which is composed by three different breeding lines: the cytoplasmic male sterility (CMS) line (A line), the maintainer line (B line), and the restorer line (R line), is a main system in hybrid rice production.
How many types of male sterility are there?
three basic
There are three basic types of male sterility, viz.: There are two other types, viz., chemical induced male sterility, and transgenic male sterility. Almost all crop plants possess male sterility if investigated property.
Which gene is responsible for male sterility?
In the mitochondrial genome of Chinsurah Boro II, a chimeric gene called orf79, located downstream of e atp6, which encodes a cytotoxic peptide, was confirmed to be responsible for the gametophytic male sterility of CMS-BT rice by transgenic experiments (Iwabuchi et al., 1993; Akagi et al., 1994; Wang et al., 2006b).
What is meant by CMS line?
What are the three line system?
In three line system of hybrid rice variety development system, three lines, A, B and R are required. A line is the cytoplasm-genetic male sterile line where the male sterility is jointly controlled by recessive nuclear gene and sterile cytoplasm.
Who is father of plant breeding?
Gregor Mendel
In the mid-1800s Gregor Mendel outlined the principles of heredity using pea plants and thus provided the necessary framework for scientific plant breeding.
What is the role of ribonuclease P?
Ribonuclease P (RNase P, EC 3.1. 26.5) is the endonuclease required for generating the mature 5′ end of tRNA in all organisms; in bacteria, it is also involved in maturation of 4.5S RNA, transfer-messenger RNA (tmRNA), and several other small RNAs (for reviews, see, e.g., Refs. 1–3).