A MADS-Box Gene-Based InDel Marker Discriminating Sex in Actinidia arguta

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The manuscript entitled “A MADS-Box Gene-Based InDel Marker Discriminating Sex in Actinidia arguta” analyzed the indel variations within sex-related genes, selected seven genes located on four sex-related genes encoding MADS-box genes, and developed a specific indel marker to discriminate sex in kiwifruit. In summary, this MS attempted to obtain an indel marker, which may helpful in understanding sex differentiation and accelerating breeding of kiwifruits. Therefore, the MS is deserved to be published in Horticulturae with minor modifications.

 

Generally, the PCR products obtained from the indel marker should be detected through 8% polyacrylamide genes after electrophoresis rather than agarose gel electrophoresis.

In Figure 2, there is a band of approximately 500 bp for female ‘Ilse’, please provide an interpretation.

Comments on the Quality of English Language

Minor editing of English language required.

Author Response

Thank you for your suggestions on our manuscript.

While we understand the advantages of 8% polyacrylamide gels, agarose gel electrophoresis can also be a cost-effective method for detecting InDel polymorphisms. Many studies have utilized agarose gel electrophoresis for detecting InDel variations.

The amplification of the ~500 bp DNA fragment in the female ‘Ilse’ may be due to the presence of a complementary genomic region. Although a non-targeted DNA fragment was generated in the female ‘Ilse’, no male-specific amplicon was observed. Consequently, the InDel marker, CBk25id01, has potential utility for sex determination in Actinidia arguta. We have additionally described this interpretation in Lines 279-282.

Reviewer 2 Report

Comments and Suggestions for Authors

The content of this study is interesting and very meaningful, but there are some problems that need to be solved. Now, most of my comments are relatively minor, but a number of aspects of the manuscript are not clear and need to be improved.

 

Major comments:

1.     Raw sequencing data needs to be uploaded to a public database.

2.     Kiwifruit (Actinidia spp.), a dioecious plant, also follows XY sex determination system. However, in table 1, why is there no one-to-one correspondence between the male and female single plants sampled?

3.     How did the authors determine that MADS genes were sex-related genes? Is there any other literature supporting or transgenic validation?

 

Minor comments:

1.     In line 240, "The eight sex-related" needs to be followed by were. Also, species need italics, such as ginkgo, date palm, asparagus, spinach.

2.     In line 277, Is there any corresponding literature support here?

3.     The grammar and tense of the article need to be carefully checked and modified.

Comments on the Quality of English Language

The paper needs revision and polishing

Author Response

Thank you for your suggestions on our manuscript. We have edited the manuscript to reflect your comments. We have responded to your review comments below.

 

Major comments:

1. Raw sequencing data needs to be uploaded to a public database.

Raw sequencing data is being uploading to the NCBI SRA database, but one weeks of additional time is required to complete the submission of sequencing data. Please allow additional time to complete data submission to NCBI.

2. Kiwifruit (Actinidia spp.), a dioecious plant, also follows XY sex determination system. However, in table 1, why is there no one-to-one correspondence between the male and female single plants sampled?

Although we have performed resequencing using represent female and male accessions included in the core set of Actinidia arguta [20], the InDel marker could discriminate female and male A. arguta accessions displayed in Table 1.  

3. How did the authors determine that MADS genes were sex-related genes? Is there any other literature supporting or transgenic validation?

The MADS-box genes have been known to involve in floral sex differentiation in kiwifruit [19]. Moreover, the MADS-box genes are included in the ABCDE model that regulates floral organ development [39]. In addition, Varkonyi-Gasic et al. [40] identified and functionally characterized MADS-box genes in kiwifruit. Particularly, in a transgenic Arabidopsis plant, which was over-expressed agamous MADS box gene isolated from Actinidia chinensis flower resulted in earlier flowering compared to the wile-type plant. Their findings suggested that agamous MADS box gene significantly influences floral organ development. We have further elaborated on this in Lines 263-265.

 

Minor comments:

1. In line 240, "The eight sex-related" needs to be followed by were. Also, species need italics, such as ginkgo, date palm, asparagus, spinach.

We have added “The eight sex-related genes” and specified scientific names of ginkgo, date palm, asparagus, and spinach in Lines 241-244. Because the ginkgo, date palm, asparagus, and spinach are their respective English names, we have italicized their scientific names alongside them.

2. In line 277(=279), Is there any corresponding literature support here?

We have added supporting literature in Line 285.

3. The grammar and tense of the article need to be carefully checked and modified.

We have checked grammar and tense of the manuscript.

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The author adds all amendments, I have no further comments