图4. DOG1表达和功能的调节（引自NONOGAKI^[91]）
A：DOG1的结构。顶部：具有外显子（E1、E2、E3）和内含子（I1、I2）的DOG1基因组DNA。可变剪接区域用粉红色和橙色作标记。表明dog1突变（dog1-3、dog1-4和dog1-5中的T-DNA,以及dog1-1中的单个碱基缺失（-C））的大致位置。中部：可变的DOG1转录物（α、β、γ、δ、ε）和相应的蛋白。注意DOG1-ε不是一个真正意义上的可变剪接产物。底部：可变多腺苷酸化的短DOG1（shDOG1,与DOG1-ε相同）和长DOG1（lgDOG1,包括DOG1-α、DOG1-β、DOG1-γ和DOG1-δ）转录物。转录起始（TSS）和终止（TTS）位点被表明。反义DOG1（asDOG1）的大致位置和方向用蓝色箭头标明。B：AsDOG1功能的可能机制。相对稳定的asDOG1 RNA可能以一种序列专一的方式或者通过它的二级结构作为一种调节RNA起作用,用于RNA介导的染色质重塑（右图,反式调节）。然而,等位基因专一的asDOG1的表达已经表明asDOG1在顺式调节中起作用（左图）。转录本身的“行为”而不是转录产物（RNA）发挥asDOG1的表达对DOG1表达和休眠的负面作用。反义表达可能引起转录干扰和影响转录延伸,这对DOG1表达和种子休眠是重要的;而转录介导的染色质重塑也是可能的。AS：可变剪接;APA：可变多腺苷酸化;Dist：远端;Prox：近段;Prot：蛋白;Tran：转录物

Fig. 4. Regulation of DOG1 expression and function (From NONOGAKI^[91])
A: Structures of the DOG1 gene. Top: DOG1 gDNA with exons (E1, E2, E3) and introns (I1, I2). Alternatively spliced regions are highlighted in pink and orange. Approximate positions of the dog1 mutations (T-DNAs in dog1-3, dog1-4, dog1-5 and a single-base deletion [-C] in dog1-1) are also indicated. Middle: Alternative DOG1 transcripts (α, β, γ, δ, ε) and the corresponding proteins. Note that DOG1-ε is not exactly an alternative splicing product. Bottom: Alternatively polyadenylated short DOG1 (shDOG1), which is identical to DOG1-ε and long (lgDOG1) transcripts, which comprises DOG1-α, -β, -γ and -δ. The transcriptional start (TSS) and termination (TTS) sites are indicated. Approximate position and the orientation of antisense DOG1 (asDOG1) are shown as a blue arrow. B: Possible mechanisms of asDOG1 function. Relatively stable asDOG1 RNA could function as a regulatory RNA, in a sequence-specific manner or through its secondary structure, for RNA-mediated chromatin remodeling (right panel, trans regulation). However, allele-specific asDOG1 expression has indicated that asDOG1 functions in cis (left panel). The “act” of transcription itself, rather than its product (RNA), exerts the negative effects of asDOG1 expression to DOG1 expression and dormancy. Antisense expression could cause transcriptional interference and affect transcription elongation, which is known to be important for DOG1 expression and seed dormancy while transcription-mediated chromatin remodeling is also possible. AS: Alternative splicing; APA: Alternative polyadenylation; Dist: Distal; Prox: Proximal; Prot: Protein; Tran: Transcription