You isolate the LLS gene from a plant that is homozygous for an S allele. To det

Question

You isolate the LLS gene from a plant that is homozygous for an S allele. To determine if and how the LLS gene acts in self incompatibility, you transfer this gene and its promoter into a plant containing S3 and S4 alleles Crosses are done between non-transgenic plants of known S allele composition and S3 S4 transgenic plants containing the LLS gene (T-S3 S4). The following results are obtained. Assume that the LLS transgene is expressed at a normal level in the transgenic plant. Based on these experiments, discuss the role of the LLS gene in self incompatibility What is the S allele specificity of the LLS gene. Explain your answers using the space below

Explanation / Answer

LSS gene self incompatinility :- Self incompatibility means if it any allele comes with the same allele then it will not express it self . If we are talking about LSS gene incompatibility thten it means If LSS gene is present in any plant and crossed with some other plant having same gene then it would not be expressed in the the next genertion.

As per the question , we transfer the LSS gene in a plant containing S3 S4 gene to get a transgenic plant.

Now this transgenic plant containing LSS (T-S3 S4) gene is crossed with a non transgenic plant containing S3 S4 gene and we get many different results,as given below-

Such that[ LSS gene containing plant is homozygous for S allele and in such condition it shows self incompatibility.]

There fore [Heterozygous condition = seed produced

Homozygous condtion = no seed]

1. female(S1 S2) cross with male (T-S3 S4)

Here seed produced .This is because these are two different alleles means heterozygous condition so that LSS gene self incompatibility does not come in function.

2. female (S2S3) crossed with male (T-S3 S4)

In this case seeds are produced because of being different gene that is heterozygous condition, LSS gene do not supress the seed formation .

3. Female(S3 S4) crossed with male (T-S3 S4)

In this case LSS (T-S3 S4) gene play its role of self incompatibility , this is a homozygous condition. when they are crossed same genes were present so that no seed formation ocurrs.

4. Female(T-S3 S4) crossed with male (S1 S2)

In this case too the genes present on female cromosome and male chromosomes are not same that is heterozygous condition so that incompatibility problem does not occur and seed formation takes place.

5.Female (S3 S4) crossed with male(S2 S3)

In this case the one allele on a chromosome is same as one allele on the male chromosome that is S3, such that LSS gene will not permit the seed formation and no seed is poduced in this case.(heterozygous condition for one alelle) .

*[Alelles: two allleles in pair form a gene and gene or alleles are present on the chromosome.

example S2 S3 are two allels of a gene].

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.