Fly: X Chromsome imblance

1. For somatic cells

X Chromsome Dosage Compensation: sovle the imblance of X-chromosome in somatic cells between female and male

In male somatic cells, the transcriptions of genes in X-chromosome will be increased to approximately twofold by MSL-complex.

https://journals.biologists.com/dev/article/136/9/1399/65536/Drosophila-dosage-compensation-a-complex-voyage-to

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https://www.nature.com/articles/nrg3124

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http://flybase.org/reports/FBgg0000283

MSL: Male-specific lethal complex

The Male Specific Lethal (MSL) complex is a chromatin modifying complex composed of five protein subunits and two non-coding RNAs. MSL is involved in X chromosome dosage compensation in males.

2. For germline cells

Meiotic Sex Chromesome Inactivation: solve the imblance of X-chromosome in postmeiotic male germ cells

In fly male postmeiotic germline cells, the X chrosomes will be silenced.

https://journals.plos.org/plosbiology/article?id=10.1371/journal.pbio.0050273

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However, unlike mammalian, the Y chromosome in postmeiotic male gremline cells is maximally active.

https://www.nature.com/articles/s41467-021-20897-y

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