Fertility restorer Indian mustard | BCH-LMO-SCBD-115910 | Living Modified Organism | Biosafety Clearing-House


Living Modified Organism (LMO)

Decisions on the LMO Risk Assessments  
last updated: 23 Feb 2021
Living Modified Organism identity
The image below identifies the LMO through its unique identifier, trade name and a link to this page of the BCH. Click on it to download a larger image on your computer. For help on how to use it go to the LMO quick-links page.
Fertility restorer Indian mustard
modbs 2.99
The Indian mustard (Brassica juncea) was modified for restoring male fertility and herbicide tolerance. For male fertility restoration, the mustard expresses Bacillus amyloliquefaciens barstar, a protein inhibitor of barnase, in the tapetum cell layer of the pollen sac during anther development. Barnase is an RNase, which degrades RNA in the pollen and prevents the pollen from developing. With barstar expression, the RNase is inhibited and the pollen develops normally. Thus, crossing barstar expressing lines with barnase expressing (male sterile) lines restores male fertility in the progeny.

For glufosinate tolerance, the mustard expresses Streptomyces hygroscopicus phosphinothricin N-acetyltransferase, which inactivates the herbicide through acetylation.

To achieve the fertility restorer line EH-2 modbs 2.99 for hybrid seed production, the mustard variety Varuna was initially transformed with transgenic construct and then backcrossed into variety EH-2. Six backcrossings were performed to try to remove integration of vector backbone sequence.
The term “Recipient organism” refers to an organism (either already modified or non-modified) that was subjected to genetic modification, whereas “Parental organisms” refers to those that were involved in cross breeding or cell fusion.
  • BCH-ORGA-SCBD-115905-1 Organism Brassica juncea (Indian mustard, Brown mustard, Chinese mustard, Leaf mustard, Vegetable mustard, Mustard greens, BRAJU)
Varuna (T-59) is extensively cultivated in northern India. EH-2 was developed from east European material by University of Nagpur.
Characteristics of the modification process
  • Agrobacterium-mediated DNA transfer
Some of these genetic elements may be present as fragments or truncated forms. Please see notes below, where applicable.
  • BCH-GENE-SCBD-100271-5 Octopine Synthase Gene Terminator | Agrobacterium tumefaciens (Agrobacterium)
  • BCH-GENE-SCBD-14972-12 Phosphinothricin N-acetyltransferase gene | Streptomyces hygroscopicus (STRHY)
    Protein coding sequence | Resistance to herbicides (Glufosinate)
  • BCH-GENE-SCBD-100366-6 CaMV Enhanced 35S promoter | Cauliflower mosaic virus (CaMV)
  • BCH-GENE-SCBD-101407-6 pTA29 pollen specific promoter | Nicotiana tabacum (Tobacco, TOBAC )
  • BCH-GENE-SCBD-14974-7 Barstar | Bacillus amyloliquefaciens (BACAM)
    Protein coding sequence | Changes in physiology and/or production (Fertility restoration)
  • BCH-GENE-SCBD-100290-6 CaMV 35S terminator | Cauliflower mosaic virus (CaMV)
The modified mustard contains two gene cassettes: Streptomyces hygroscopicus (bar) and Bacillus amyloliquefaciens barstar.

The bar coding sequence is under control of the Cauliflower mosaic virus (CaMV) enhanced 35S promoter and Rhizobium radiobacter octopine synthase terminator.

Barstar is under control of a Nicotiana tabacum TA29 pollen specific promoter and a CaMV 35S terminator. The TA29 promoter is active only in the tapetum cell layer of the pollen sac during anther development (male-specific expression). The coding sequence was codon optimized for expression in plants.

- Southern blot and segregation analyses indicated that the genome contains a single insertion
- DNA sequence analysis indicated that the insertion occurred in the 'B' genome.
LMO characteristics
  • Other (Hybrid seed production)
Detection method(s)
Additional Information